RFR: 2111: Normalize usernames before comparing

[Zhao Song]

In https://github.com/openjdk/jdk/pull/16788#issuecomment-1827984539, although the user's full name and the head commit author's name seems exactly same in the GitHub. The bot was thinking they are different, Erik pointed out the root cause "The problem was that a unicode character was encoded differently, one as a composition and one as a single character. "

To avoid this kind of problems in the future, we should normalize the strings before comparison to ensure unicode characters are encoded in the same way.

-------------

Commit messages:
 - SKARA-2111

Changes: https://git.openjdk.org/skara/pull/1591/files
 Webrev: https://webrevs.openjdk.org/?repo=skara&pr=1591&range=00
  Issue: https://bugs.openjdk.org/browse/SKARA-2111
  Stats: 6 lines in 1 file changed: 4 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/skara/pull/1591.diff
  Fetch: git fetch https://git.openjdk.org/skara.git pull/1591/head:pull/1591

PR: https://git.openjdk.org/skara/pull/1591