No longer crash if no incompatible flags were found (#1164)

In the new world of LTS and rolling releases we no longer require incompatible flag issues.
Consequently, we should not crash if there are no such flags.

This is a temporary workaround for https://github.com/bazelbuild/bazel/issues/13524.
In the long term we probably want to get rid of the incompatible flag code completely.
1 file changed