ci: bump bazel

[zirain]

Commit Message: istio proxy failed to build with bazel 7.1.2, and passed with 7.2.0, see istio/proxy#6023
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[phlax]

@zirain as you can see from the CI this is not currently possible due to a bazel bug which causes our mobile/coverage to fail

7.1.2 is as high as we can go with current bazel so we will need to either jump to 8 or >7.5 if the bugfix is backported

this is the bug - bazelbuild/bazel#23247

out of interest does bumping the bazel version fix the issue istio has?

[zirain]

istio/proxy#6023 showed that bumping the bazel will help.

I can give a try with 7.5+

[phlax]

cc @keith

[zirain]

failed with bazel 8 and expected first release candidate date if 7.5 is 2025-01-13.

[phlax]

cc @keith wondering if we can get the fix included in the 7.5 release

@zirain one workaround might be for istio to adjust the bazel version in a patch - i think that wont break anything altho not 100%

[zirain]

@zirain one workaround might be for istio to adjust the bazel version in a patch - i think that wont break anything altho not 100%

I commented the sync code of .bazelversion file, so it won't be a blocker.
It would be better we can enable it soon.

[zirain]

closed as #37864.