RFR: 8305527: HarfBuzz: Remove trailing comma from the enum in hb-paint.h

[Dmitry Markov]

Port the fix from the upstream/HarfBuzz repo.

More info can be obtained here:
https://github.com/harfbuzz/harfbuzz/discussions/4188 
https://github.com/harfbuzz/harfbuzz/commit/04a47932a3844f7e73e3af8b05fb98c8b54fb779

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Commit messages:
 - 8305527: HarfBuzz: Remove trailing comma from the enum in hb-paint.h

Changes: https://git.openjdk.org/jdk/pull/13328/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13328&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8305527
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/13328.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13328/head:pull/13328

PR: https://git.openjdk.org/jdk/pull/13328