[jdk23u] RFR: 8339644: Improve parsing of Day/Month in tzdata rules

[Johny Jose]

clean backport of https://github.com/openjdk/jdk/commit/86a2f9c7dcb6585cabf03c0940511d11560e85b7

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

Commit messages:
 - Backport 86a2f9c7dcb6585cabf03c0940511d11560e85b7

Changes: https://git.openjdk.org/jdk23u/pull/159/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk23u&pr=159&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8339644
  Stats: 83 lines in 3 files changed: 23 ins; 26 del; 34 mod
  Patch: https://git.openjdk.org/jdk23u/pull/159.diff
  Fetch: git fetch https://git.openjdk.org/jdk23u.git pull/159/head:pull/159

PR: https://git.openjdk.org/jdk23u/pull/159