RFR: 8371163: Make GlyphView/TestGlyphBGHeight.java headless

[Prasanta Sadhukhan]

Test is made headless

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Commit messages:
 - 8371163: Make GlyphView/TestGlyphBGHeight.java headless

Changes: https://git.openjdk.org/jdk/pull/28173/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28173&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8371163
  Stats: 66 lines in 1 file changed: 15 ins; 22 del; 29 mod
  Patch: https://git.openjdk.org/jdk/pull/28173.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28173/head:pull/28173

PR: https://git.openjdk.org/jdk/pull/28173