RFR: 1830: Support wildcard branch protection with prbranches

[Zhao Song]

In this patch, notifyBot would add wildcard branch protection for the repo, and when the bot tries to delete the pr/* branch, it will temporarily remove wildcard branch protection.

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Commit messages:
 - fix a problem
 - fix import
 - SKARA-1830

Changes: https://git.openjdk.org/skara/pull/1489/files
 Webrev: https://webrevs.openjdk.org/?repo=skara&pr=1489&range=00
  Issue: https://bugs.openjdk.org/browse/SKARA-1830
  Stats: 22 lines in 2 files changed: 17 ins; 5 del; 0 mod
  Patch: https://git.openjdk.org/skara/pull/1489.diff
  Fetch: git fetch https://git.openjdk.org/skara.git pull/1489/head:pull/1489

PR: https://git.openjdk.org/skara/pull/1489