RFR: 8336815: Socket.bind/connect and ServerSocket.bind/accept do not specify behavior when already bound, connected or closed [v2]

[Jaikiran Pai]

> Can I please get a review of this change which updates the specification of a few methods in `java.net.Socket` and `java.net.ServerSocket` classes to specify the `IOException` that the implementation currently already throws?
> 
> This is merely a doc update and doesn't change the implementation.
> 
> Given that these exceptions can now be asserted, a new jtreg test has been introduced to verify the exceptions thrown from these APIs. The test passes. tier testing is currently in progress. I'll open a CSR shortly.

Jaikiran Pai has updated the pull request incrementally with one additional commit since the last revision:

  Alan's suggestion - is not instead of isn't and closed instead of already closed

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Changes:
  - all: https://git.openjdk.org/jdk/pull/20268/files
  - new: https://git.openjdk.org/jdk/pull/20268/files/6cee1c9d..8990787f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20268&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20268&range=00-01

  Stats: 3 lines in 2 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/20268.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20268/head:pull/20268

PR: https://git.openjdk.org/jdk/pull/20268