RFR: 8296529: Document the default behavior of '$' in regular expressions correctly

[Raffaello Giulietti]

A small spec change to match established behavior.

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Commit messages:
 - 8296529: Document the default behavior of '$' in regular expressions correctly

Changes: https://git.openjdk.org/jdk/pull/11038/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11038&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8296529
  Stats: 3 lines in 1 file changed: 2 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/11038.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11038/head:pull/11038

PR: https://git.openjdk.org/jdk/pull/11038