RFR: 8285962: NimbusDefaults has a typo in a L&F property

[Prasanta Sadhukhan]

BasicLookAndFeel, BasicProgressBarUI, GTKLookAndFeel tries to find property by "ProgressBar.verticalSize" but the property defined in NimbusDefaults has a typo "vertictalSize ".
Rectified the typo.

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

Commit messages:
 - 8285962: NimbusDefaults has a typo in a L&F property

Changes: https://git.openjdk.java.net/jdk/pull/8504/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8504&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8285962
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8504.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8504/head:pull/8504

PR: https://git.openjdk.java.net/jdk/pull/8504