chore: bump Bazel to 9.0.1

[gregmagolan]

Bumps .bazelversion from 8.5.1 to 9.0.1 in the root workspace, e2e/, and examples/dev_deps/.

e2e/cases/repository-rule-deps-299/.bazelversion is left at 7.1.0 intentionally as it tests older Bazel compatibility.

[jbedard]

e2e/cases/repository-rule-deps-299/.bazelversion is left at 7.1.0 intentionally as it tests older Bazel compatibility.

Doesn't workflows ignore the .bazelversion and explicitly tests 8.x and 9.x. So I think the local .bazelverison files are basically just the default version used by devs and this PR doesn't effect CI? That's why in most rulesets all the e2e tests just symlink to the root .bazelversion...

[aspect-workflows]

Bazel 8 (Test)

All tests were cache hits

111 tests (100.0%) were fully cached saving 56s.

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Bazel 9 (Test)

All tests were cache hits

111 tests (100.0%) were fully cached saving 59s.

---

Bazel 8 (Test)

e2e

All tests were cache hits

51 tests (100.0%) were fully cached saving 40s.

---

Bazel 9 (Test)

e2e

1 test target passed

Targets

//cases/interpreter-version-541:test_3_9_classic [k8-fastbuild-ST-cc09ec9be975]560ms

Total test execution time was 560ms. 50 tests (98.0%) were fully cached saving 59s.

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Bazel 8 (Test)

examples/uv_pip_compile

All tests were cache hits

1 test (100.0%) was fully cached saving 444ms.

[gregmagolan]

e2e/cases/repository-rule-deps-299/.bazelversion is left at 7.1.0 intentionally as it tests older Bazel compatibility.

Doesn't workflows ignore the .bazelversion and explicitly tests 8.x and 9.x. So I think the local .bazelverison files are basically just the default version used by devs and this PR doesn't effect CI? That's why in most rulesets all the e2e tests just symlink to the root .bazelversion...

Yeah. Looks like we're explicitly setting USE_BAZEL_VERSION on CI so we never test with Bazel 7 anyway 🤷

[jbedard]

So lets make every .bazelversion symlink to the root and only update in one place?