chore: use bzlmod override_repo() to replace go.mod with bzlmods

[jbedard]

This might be nice for root repos, I'm uncertain if this is a good idea for bzlmods meant to be published+used?

Changes are visible to end-users: no

Test plan

• Covered by existing test cases

[aspect-workflows]

Test

All tests were cache hits

2 tests (100.0%) were fully cached saving 90ms.

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Test

language/js

All tests were cache hits

111 tests (100.0%) were fully cached saving 22s.

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Test

language/kotlin

All tests were cache hits

19 tests (100.0%) were fully cached saving 4s.

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Test

language/orion

All tests were cache hits

43 tests (100.0%) were fully cached saving 9s.

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Test

runner

All tests were cache hits

19 tests (100.0%) were fully cached saving 2s.

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Buildifier      Gazelle      Gazelle [language/js]      Gazelle [language/kotlin]      Gazelle [language/orion]      Gazelle [runner]