Issues noted in PRs that are not there

[gudmdharalds]

In some circumstances vip-go-ci can note internally that a Pull-Request has an inline comment to a review already submitted to it, when it really does not, but another Pull-Request referring to the same commit-ID has. This can cause vip-go-ci not to publish a PHPCS issue to a review during the execution (for instance), as the logic tries to avoid double-posting the same issue twice. This only affects Pull-Requests that share one or more commits between them.

Replication

1. Create two Pull-Requests that refer to the same commit-ID with problems that PHPCS should note.
2. Turn off PHPCS scanning for one of the Pull-Requests, for instance via label that indicates to skip scanning, but not for the other.
3. Run vip-go-ci for the commit-ID.
4. See comments being sent to one Pull-Request but not the other, as expected.
5. Remove label that indicates skip of PHPCS scanning. Run vip-go-ci again for the commit.
6. Note that review comments are not sent to the Pull-Request that had missing PHPCS comments earlier, although they should by now.