RFR: 660: Add blank line prior to PR body HTML comment

[Erik Helin]

Hi all,

please review this patch that adds a newline (a blank line) prior to the bots `` message. This is needed to avoid bad
interactions with GitHub's Markdown parser for some of the more esoteric Markdown features of GitHub Flavored Markdown.

Testing:
- [x] `make test` passes on Linux x64
- [x] `make images` passes on Linux x64

Thanks,
Erik

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Commit messages:
 - 660

Changes: https://git.openjdk.java.net/skara/pull/824/files
 Webrev: https://webrevs.openjdk.java.net/?repo=skara&pr=824&range=00
  Issue: https://bugs.openjdk.java.net/browse/SKARA-660
  Stats: 2 lines in 2 files changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/skara/pull/824.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/824/head:pull/824

PR: https://git.openjdk.java.net/skara/pull/824