RFR: Ensure that a check that no longer requires a refresh is removed from the list

[Robin Westberg]

When a check transitions from needing a periodic refresh to stable, it should be removed from the list of PRs that needs a refresh.

-------------

Commit messages:
 - Ensure that a check that no longer requires a refresh is removed from the list

Changes: https://git.openjdk.java.net/skara/pull/942/files
 Webrev: https://webrevs.openjdk.java.net/?repo=skara&pr=942&range=00
  Stats: 3 lines in 1 file changed: 2 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/skara/pull/942.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/942/head:pull/942

PR: https://git.openjdk.java.net/skara/pull/942