[jdk20] RFR: 4958969: ObjectOutputStream example leads to non-working code

[Roger Riggs]

Update javadoc examples to use try-with-resources and use javadoc snippet tags.
The examples in ObjectInputStream and ObjectOutputStream get an update with
try-with-resources and use of javadoc snippet tags.
ObjectInputFilter is updated with use of snippet tags instead of html markup.

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Commit messages:
 - 4958969: ObjectOutputStream example leads to non-working code

Changes: https://git.openjdk.org/jdk20/pull/59/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk20&pr=59&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-4958969
  Stats: 61 lines in 3 files changed: 1 ins; 3 del; 57 mod
  Patch: https://git.openjdk.org/jdk20/pull/59.diff
  Fetch: git fetch https://git.openjdk.org/jdk20 pull/59/head:pull/59

PR: https://git.openjdk.org/jdk20/pull/59