Merge branch 'hi/merge-verify-sig-config'

"git merge" learned to pay attention to merge.verifySignatures configuration variable and pretend as if '--verify-signatures' option was given from the command line. * hi/merge-verify-sig-config: t5573, t7612: clean up after unexpected success of 'pull' and 'merge' t: add tests for pull --verify-signatures merge: add config option for verifySignatures