Do not emit solver errors that contain error types

[oli-obk]

any follow-up errors are going to either be duplicates or often disappear if the error itself is fixed.

in this PR it mostly silences dyn-compat errors as all the other errors are already deduplicated outside of the test suite. The dyn compat errors are independent errors and I think if the dyn compatiblity depended on an error type it would not actually show, so this is PR is actually silencing independent errors, too.

I am opening this PR because I am seeing lots of {type error}: const Trait errors when adding more const checking. So instead of targetting just those specific errors, I wanted to try out fully avoiding such errors near the trait solver.

cc @rust-lang/types for thoughts

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[rust-log-analyzer]

The job aarch64-gnu-llvm-20-1 failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

30 
- error[E0107]: associated type takes 1 lifetime argument but 0 lifetime arguments were supplied
-   --> $DIR/invalid_const_in_lifetime_position.rs:4:26
-    |
- LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
-    |                          ^ expected 1 lifetime argument
-    |
- note: associated type defined here, with 1 lifetime parameter: `'a`
-   --> $DIR/invalid_const_in_lifetime_position.rs:2:10
-    |
- LL |     type Y<'a>;
-    |          ^ --
-    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
- help: add missing lifetime argument
-    |
- LL | fn f<'a>(arg : Box<dyn X<Y<'_, 1> = &'a ()>>) {}
-    |                            +++
+ error: aborting due to 2 previous errors
47 
- error[E0107]: associated type takes 0 generic arguments but 1 generic argument was supplied
-   --> $DIR/invalid_const_in_lifetime_position.rs:4:26
-    |
- LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
-    |                          ^--- help: remove the unnecessary generics
-    |                          |
-    |                          expected 0 generic arguments
-    |
- note: associated type defined here, with 0 generic parameters
-   --> $DIR/invalid_const_in_lifetime_position.rs:2:10
-    |
- LL |     type Y<'a>;
-    |          ^
-    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
- 
- error[E0107]: associated type takes 1 lifetime argument but 0 lifetime arguments were supplied
-   --> $DIR/invalid_const_in_lifetime_position.rs:4:26
-    |
- LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
-    |                          ^ expected 1 lifetime argument
-    |
- note: associated type defined here, with 1 lifetime parameter: `'a`
-   --> $DIR/invalid_const_in_lifetime_position.rs:2:10
-    |
- LL |     type Y<'a>;
-    |          ^ --
-    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
- help: add missing lifetime argument
-    |
- LL | fn f<'a>(arg : Box<dyn X<Y<'_, 1> = &'a ()>>) {}
-    |                            +++
- 
- error[E0107]: associated type takes 0 generic arguments but 1 generic argument was supplied
-   --> $DIR/invalid_const_in_lifetime_position.rs:4:26
-    |
- LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
-    |                          ^--- help: remove the unnecessary generics
-    |                          |
-    |                          expected 0 generic arguments
-    |
- note: associated type defined here, with 0 generic parameters
-   --> $DIR/invalid_const_in_lifetime_position.rs:2:10
-    |
- LL |     type Y<'a>;
-    |          ^
-    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
- 
- error[E0038]: the trait `X` is not dyn compatible
-   --> $DIR/invalid_const_in_lifetime_position.rs:4:20
-    |
- LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
-    |                    ^^^^^^^^^^^^^^^^^^^^ `X` is not dyn compatible
-    |
- note: for a trait to be dyn compatible it needs to allow building a vtable
-       for more information, visit <https://doc.rust-lang.org/reference/items/traits.html#dyn-compatibility>
-   --> $DIR/invalid_const_in_lifetime_position.rs:2:10
-    |
- LL | trait X {
-    |       - this trait is not dyn compatible...
- LL |     type Y<'a>;
-    |          ^ ...because it contains the generic associated type `Y`
-    = help: consider moving `Y` to another trait
- 
- error: aborting due to 7 previous errors
- 
- Some errors have detailed explanations: E0038, E0107.
- For more information about an error, try `rustc --explain E0038`.
---
To only update this specific test, also pass `--test-args invalid_const_in_lifetime_position.rs`

error: 1 errors occurred comparing output.
status: exit status: 1
command: env -u RUSTC_LOG_COLOR RUSTC_ICE="0" RUST_BACKTRACE="short" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2/bin/rustdoc" "/checkout/tests/rustdoc-ui/invalid_const_in_lifetime_position.rs" "-Zthreads=1" "-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX" "-Ztranslate-remapped-path-to-local-path=no" "-Z" "ignore-directory-in-diagnostics-source-blocks=/cargo" "-Z" "ignore-directory-in-diagnostics-source-blocks=/checkout/vendor" "--sysroot" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2" "--target=aarch64-unknown-linux-gnu" "--check-cfg" "cfg(test,FALSE)" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zwrite-long-types-to-disk=no" "-Cstrip=debuginfo" "-o" "/checkout/obj/build/aarch64-unknown-linux-gnu/test/rustdoc-ui/invalid_const_in_lifetime_position" "-A" "internal_features" "-A" "unused_parens" "-A" "unused_braces" "-Cdebuginfo=0"
stdout: none
--- stderr -------------------------------
error[E0107]: associated type takes 1 lifetime argument but 0 lifetime arguments were supplied
##[error]  --> /checkout/tests/rustdoc-ui/invalid_const_in_lifetime_position.rs:4:26
   |
LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
   |                          ^ expected 1 lifetime argument
   |
note: associated type defined here, with 1 lifetime parameter: `'a`
  --> /checkout/tests/rustdoc-ui/invalid_const_in_lifetime_position.rs:2:10
   |
LL |     type Y<'a>;
   |          ^ --
help: add missing lifetime argument
   |
LL | fn f<'a>(arg : Box<dyn X<Y<'_, 1> = &'a ()>>) {}
   |                            +++

error[E0107]: associated type takes 0 generic arguments but 1 generic argument was supplied
##[error]  --> /checkout/tests/rustdoc-ui/invalid_const_in_lifetime_position.rs:4:26
   |
LL | fn f<'a>(arg : Box<dyn X<Y<1> = &'a ()>>) {}
   |                          ^--- help: remove the unnecessary generics
   |                          |
   |                          expected 0 generic arguments
   |
note: associated type defined here, with 0 generic parameters
  --> /checkout/tests/rustdoc-ui/invalid_const_in_lifetime_position.rs:2:10

[jackh726]

Seems reasonable - the presence of an error type means that there will be some diagnostic emitted, and that's likely going to be closer to the "root cause"