fix(bazel extractor): better handling of bazel exit code (#3921)
fix(bazel extractor): better handling of bazel exit code (#3921)

We use the --keep_going flag so that we can extract all buildable targets even if some targets fail.
If bazel fails to build some packages, but otherwise succeeds in extracting, the exit code is 1. Other errors like "bazel server died unexpectedly" give other exit codes and will now cause the
extractor script to fail.

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