RFR: 1539: Allow dots in merge PR branch name

Thu Aug 11 13:55:36 UTC 2022

This patch makes it possible to create merge style PRs based on branches with periods `.` in the branch name. We quite commonly put periods in branch names as we like to base branches on version strings.

Modified an existing test to cover this case.

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Commit messages:
 - SKARA-1539

Changes: https://git.openjdk.org/skara/pull/1355/files
 Webrev: https://webrevs.openjdk.org/?repo=skara&pr=1355&range=00
  Issue: https://bugs.openjdk.org/browse/SKARA-1539
  Stats: 9 lines in 2 files changed: 0 ins; 0 del; 9 mod
  Patch: https://git.openjdk.org/skara/pull/1355.diff
  Fetch: git fetch https://git.openjdk.org/skara pull/1355/head:pull/1355

PR: https://git.openjdk.org/skara/pull/1355