Links should not Serde deserialize into bytes

[vmx]

When using the Ipld::Link type, it should not be possible to accidentally deserialize it into bytes. The ipld_deserialize_link_not_as_bytes test is there in order to make sure it hold up.

With recent Rust versions, this behaviour changes. To reproduce the issue:

$ cargo +1.72.0 test --features serde-codec --test serde_deserialize ipld_deserialize_link_not_as_bytes
    Finished test [unoptimized + debuginfo] target(s) in 0.19s
     Running tests/serde_deserialize.rs (/home/vmx/src/pl/rust/libipld/target/debug/deps/serde_deserialize-08fc1a5973f45cb0)

running 1 test
test ipld_deserialize_link_not_as_bytes - should panic ... ok

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 13 filtered out; finished in 0.00s

passes the tests. But Rust 1.73.0 does not:

$ cargo +1.73.0 test --features serde-codec --test serde_deserialize ipld_deserialize_link_not_as_bytes
    Finished test [unoptimized + debuginfo] target(s) in 0.17s
     Running tests/serde_deserialize.rs (/home/vmx/src/pl/rust/libipld/target/debug/deps/serde_deserialize-3f5dc1e4175d950e)

running 1 test
test ipld_deserialize_link_not_as_bytes - should panic ... FAILED

failures:

---- ipld_deserialize_link_not_as_bytes stdout ----
thread 'ipld_deserialize_link_not_as_bytes' panicked at core/tests/serde_deserialize.rs:150:5:
assertion `left == right` failed
  left: [1, 85, 18, 32, 159, 228, 204, 198, 222, 22, 114, 79, 58, 48, 199, 232, 242, 84, 243, 198, 71, 25, 134, 172, 177, 248, 216, 207, 142, 150, 206, 42, 215, 219, 231, 251]
 right: bafkreie74tgmnxqwojhtumgh5dzfj46gi4mynlfr7dmm7duwzyvnpw7h7m
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
note: panic did not contain expected string
      panic message: `"assertion `left == right` failed\n  left: [1, 85, 18, 32, 159, 228, 204, 198, 222, 22, 114, 79, 58, 48, 199, 232, 242, 84, 243, 198, 71, 25, 134, 172, 177, 248, 216, 207, 142, 150, 206, 42, 215, 219, 231, 251]\n right: bafkreie74tgmnxqwojhtumgh5dzfj46gi4mynlfr7dmm7duwzyvnpw7h7m"`,
 expected substring: `"assertion failed"`

failures:
    ipld_deserialize_link_not_as_bytes

test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 13 filtered out; finished in 0.00s

error: test failed, to rerun pass `--test serde_deserialize`

[vmx]

The problem is that should_panic matches on a specific error message, which was changed in recent Rust versions.