[jdk11u-dev] RFR: 8295429: Update harfbuzz md file

[Goetz Lindenmaier]

I backport this for parity with 11.0.18-oracle.

Backport from 17 because that is clean.

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Commit messages:
 - Backport cb9289ed7589e2cfbe8ac21ab6f3039ee09216ea

Changes: https://git.openjdk.org/jdk11u-dev/pull/1493/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1493&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8295429
  Stats: 16 lines in 1 file changed: 8 ins; 0 del; 8 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1493.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev pull/1493/head:pull/1493

PR: https://git.openjdk.org/jdk11u-dev/pull/1493