RFR: Add newline after closed issue warning

[Jorn Vernee]

Adds a missing newline after the 'issue is not open' warning, which is currently missing, and leads to the list not being formatted correctly. See e.g. https://github.com/openjdk/jdk/pull/1444

![image](https://user-images.githubusercontent.com/5962029/100388139-12f8ff80-302a-11eb-876a-25943c7d75d8.png)

Any testing needed for this?

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Commit messages:
 - Add newline after closed issue warning

Changes: https://git.openjdk.java.net/skara/pull/963/files
 Webrev: https://webrevs.openjdk.java.net/?repo=skara&pr=963&range=00
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/skara/pull/963.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/963/head:pull/963

PR: https://git.openjdk.java.net/skara/pull/963