[jfx15] RFR: 8255042: Change JavaFX release version in jfx15 branch to 15.0.1

[Johan Vos]

Increase release version to 15.0.1
Fix for JDK-8255042

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

Commit messages:
 - Increase release version to 15.0.1

Changes: https://git.openjdk.java.net/jfx/pull/325/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx&pr=325&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8255042
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jfx/pull/325.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/325/head:pull/325

PR: https://git.openjdk.java.net/jfx/pull/325