RFR: Allow a source repository to be removed

[Robin Westberg]

Hi all,

Please review this small change that adds support for PRs where the source repository has been removed.

Best regards,
Robin

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Commit messages:
 - Allow the source repository to be removed

Changes: https://git.openjdk.java.net/skara/pull/708/files
 Webrev: https://webrevs.openjdk.java.net/skara/708/webrev.00
  Stats: 25 lines in 7 files changed: 10 ins; 0 del; 15 mod
  Patch: https://git.openjdk.java.net/skara/pull/708.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/708/head:pull/708

PR: https://git.openjdk.java.net/skara/pull/708