[core][devex] Move ray/util build targets to separate build files

[vitsai]

Why are these changes needed?

Some build file cleanup before we separate out into finer targets.

Related issue number

#36611

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• I've included any doc changes needed for https://docs.ray.io/en/master/.
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    method in Tune, I've added it in doc/source/tune/api/ under the
    corresponding .rst file.
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• Testing Strategy
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  • This PR is not tested :(

[raulchen]

Is there a master issue that describes this effort? e.g., what problems are we going to resolve? and the execution plan.

For this particular PR, it seems to me that the only benefit is to slim the the BUILD file. And I don't see why I can't do it in place.

[vitsai]

Created #36611 to track this.

Looks like it can be done incrementally in place after all; the mistake was putting BUILD files in the src and ray directories. Once you put a BUILD file in a directory, all targets building that subtree cannot be in a BUILD file in an ancestor of that directory.

However, it seems like there is a way to skip the src and ray directories the way the protobuf folder has done.

[scv119]

Skipping '//:logging_test': no such target '//:logging_test': target 'logging_test' not declared in package '' defined by /ray/BUILD.bazel

test failure looks related.

[pcmoritz]

Nice, it is great that you can do it without moving the source tree :)