RFR: 8340568: Incorrect escaping of single quotes when pretty-printing character literals

[Liam Miller-Cushon]

This change fixes a regression in pretty-printing of character literals after [JDK-8325078](https://bugs.openjdk.org/browse/JDK-8325078). The pretty-printed form of the character literal `'` should be `'''`, intead of `'''`.

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Commit messages:
 - formatting
 - 8340568: Incorrect escaping of single quotes when pretty-printing character literals

Changes: https://git.openjdk.org/jdk/pull/21116/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21116&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8340568
  Stats: 90 lines in 2 files changed: 89 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/21116.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21116/head:pull/21116

PR: https://git.openjdk.org/jdk/pull/21116