RFR: 6635: Add whitespace rule to JMC jcheck configuration

[Christoph Langer]

This is my first PR with skara :)

I think it would be nice if jcheck would also check for unnecessary whitespace.

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Commits:
 - e201163f: 6635: Add whitespace rule to JMC jcheck configuration

Changes: https://git.openjdk.java.net/jmc/pull/4/files
 Webrev: https://webrevs.openjdk.java.net/jmc/4/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JMC-6635
  Stats: 4 lines in 1 file changed: 3 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jmc/pull/4.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/4/head:pull/4

PR: https://git.openjdk.java.net/jmc/pull/4