chore: remove non-bzlmod dep on @internal_platforms_do_not_use//host:constraints.bzl now that root workspace is bzlmod-only

[gregmagolan]

Now that #915 landed we can remove this sadness.

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Changes are visible to end-users: no

Test plan

• Covered by existing test cases

[aspect-workflows]

Test

4 test targets passed

Targets

//lib/tests/copy_to_directory:case_22_test [k8-fastbuild]    142ms
//lib/tests/copy_to_directory_bin_action:test [k8-fastbuild] 206ms
//lib/tests/jq:check_stamped [k8-fastbuild]                  219ms
//lib/tests/yq:check_stamped [k8-fastbuild]                  359ms

Total test execution time was 926ms. 217 tests (98.2%) were fully cached saving 58s.

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Test

e2e/copy_action

All tests were cache hits

1 test (100.0%) was fully cached saving 59ms.

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Test

e2e/copy_to_directory

All tests were cache hits

6 tests (100.0%) were fully cached saving 750ms.

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Test

e2e/coreutils

All tests were cache hits

4 tests (100.0%) were fully cached saving 742ms.

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Test

e2e/external_copy_to_directory

All tests were cache hits

1 test (100.0%) was fully cached saving 59ms.

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Test

e2e/smoke

All tests were cache hits

6 tests (100.0%) were fully cached saving 1s.

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Buildifier      Format      Gazelle