[jdk11u-dev] RFR: 8229912: [TESTBUG] java/net/Socks/SocksIPv6Test fails without IPv6

[luchenlin]

I backport this for parity with 11.0.20-oracle.

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Commit messages:
 - Backport 84686488e8d10c13c30b9ad6272a2b9a4907891b

Changes: https://git.openjdk.org/jdk11u-dev/pull/1939/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1939&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8229912
  Stats: 11 lines in 1 file changed: 7 ins; 3 del; 1 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1939.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/1939/head:pull/1939

PR: https://git.openjdk.org/jdk11u-dev/pull/1939