Generate fewer targets for platform constraints

[dzbarsky]

skylib's implementation of config_setting_group is a little wild, it generates chains of selects and alias targets. We don't really need to do that, we can just declare what we want directly.

bazel query //uv/private/constraints/platform:all | wc -l drops from 12K to 5.3K. All the removed targets were private so feels like this should be fine.

Also:

before:

after:

---

Changes are visible to end-users: no

Test plan

• Covered by existing test cases

[aspect-workflows]

test-os:linux-bzl:8 (Test)

All tests were cache hits

38 tests (100.0%) were fully cached saving 50s.

---

test-os:linux-bzl:latest (Test)

All tests were cache hits

38 tests (100.0%) were fully cached saving 50s.

---

test-os:linux-bzl:8 (Test)

e2e

All tests were cache hits

14 tests (100.0%) were fully cached saving 10s.

---

test-os:linux-bzl:latest (Test)

e2e

All tests were cache hits

14 tests (100.0%) were fully cached saving 10s.

---

test-os:linux-bzl:8 (Test)

examples/uv_pip_compile

All tests were cache hits

1 test (100.0%) was fully cached saving 335ms.

---

test-os:linux-bzl:latest (Test)

examples/uv_pip_compile

All tests were cache hits

1 test (100.0%) was fully cached saving 335ms.

[arrdem]

Ah nice. We can probably apply the same optimization to the interpreter range and ABI tests.

[dzbarsky]

Ah nice. We can probably apply the same optimization to the interpreter range and ABI tests.

Sure I can look at those in a follow-up