RFR: 8299827: Add resolved IP address in connection exception for sockets [v5]

[Ralf Schmelter]

> This change adds the resolved IP address to the exception text of a failed socket connection. This helps if the connection failed because of stale DNS entries.

Ralf Schmelter has updated the pull request incrementally with one additional commit since the last revision:

  Improve exception message in test

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Changes:
  - all: https://git.openjdk.org/jdk/pull/11961/files
  - new: https://git.openjdk.org/jdk/pull/11961/files/074f212f..3cf476df

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=11961&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=11961&range=03-04

  Stats: 2 lines in 1 file changed: 0 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/11961.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11961/head:pull/11961

PR: https://git.openjdk.org/jdk/pull/11961