gopackagesdriver: ignore bazel analysis errors (#4567)

**What type of PR is this?**

> Bug fix

**What does this PR do? Why is it needed?**

Bazel exits with code 7 (ANALYSIS_FAILURE) when querying a file that's
not mentioned in BUILD. gopackagesdriver can returns partial results for
code 1 (BUILD_FAILURE), but not 7.

gopackagesdriver often hits this for a new file not added to BUILD. A
file= query may still fail in this case because the query will match no
labels, but at least that's no longer a bazel error.

**Which issues(s) does this PR fix?**

Fixes #4565

**Other notes for review**