Still link to b.p.o when both issue number and trivial label are found

[Mariatta]

For example: python/cpython#1120

It has both bpo-NNNN in the PR title and trivial label.
bedevere status check should still have details link to the said issue.

Thanks :)

[terryjreedy]

Definitely. In this case, the issue https://bugs.python.org/issue29861 and initial patch were not at all trivial, just the minor cleanup for occasional test failures reported on the issue.