<i18n dev> RFR: 8300356: Refactor code examples to use @snippet in java.text.CollationElementIterator [v2]

[Justin Lu]

> This PR implements _JEP 413: Code Snippets in Java API Documentation_ for [java.text.CollationElementIterator](https://docs.oracle.com/en/java/javase/19/docs/api/java.base/java/text/CollationElementIterator.html).
> 
> Code examples using <pre> ... </pre> blocks are replaced with the @ snippet syntax where applicable.
> 
> 
> Additionally, removed a floating colon in the code example

Justin Lu has updated the pull request incrementally with one additional commit since the last revision:

  Replace conversion cast w/ pattern matching instaceOf

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Changes:
  - all: https://git.openjdk.org/jdk/pull/12055/files
  - new: https://git.openjdk.org/jdk/pull/12055/files/be291cbc..20c18209

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12055&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12055&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/12055.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12055/head:pull/12055

PR: https://git.openjdk.org/jdk/pull/12055