RFR: forge: fix recentCommitComments for GitHub

[Erik Helin]

Hi all,

please review this patch that fixes `recentCommitComments` for `GitHubRepository` via tweaking the GraphQL query a bit.

Thanks,
Erik

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Commit messages:
 - forge: fix recentCommitComments for GitHub

Changes: https://git.openjdk.java.net/skara/pull/904/files
 Webrev: https://webrevs.openjdk.java.net/?repo=skara&pr=904&range=00
  Stats: 57 lines in 2 files changed: 17 ins; 7 del; 33 mod
  Patch: https://git.openjdk.java.net/skara/pull/904.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/904/head:pull/904

PR: https://git.openjdk.java.net/skara/pull/904