RFR: 8332623: Remove setTTL()/getTTL() methods from DatagramSocketImpl/MulticastSocket and MulticastSocket.send(DatagramPacket, byte)

[Jaikiran Pai]

Can I please get a review of this change which proposes to remove the deprecated-for-removal methods from `MulticastSocket` and `DatagramSocketImpl`? 

The following methods on `java.net.MulticastSocket` and `java.net.DatagramSocketImpl`:


public void setTTL(byte ttl) throws IOException
public byte getTTL() throws IOException


and this other one on `MulticastSocket`:


public void send(DatagramPacket p, byte ttl) throws IOException 


have been deprecated for removal since Java 23, through https://bugs.openjdk.org/browse/JDK-8332181. Even before that they have been deprecated since Java 1.2 and Java 1.4.

The commit in this PR removes them completely. This PR also removes some tests that were specifically testing the `setTTL()/getTTL()/send(DatagramPacket, byte)` methods. A few other tests have been adjusted to use the alternate `getTimeToLive()/setTimeToLive()` methods where appropriate.

Existing tests in tier1, tier2 and tier3 continue to pass with these changes.

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Commit messages:
 - 8332623: Remove setTTL()/getTTL() methods from DatagramSocketImpl/MulticastSocket and MulticastSocket.send(DatagramPacket, byte)

Changes: https://git.openjdk.org/jdk/pull/25744/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25744&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8332623
  Stats: 442 lines in 19 files changed: 12 ins; 408 del; 22 mod
  Patch: https://git.openjdk.org/jdk/pull/25744.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25744/head:pull/25744

PR: https://git.openjdk.org/jdk/pull/25744