RFR: 8338630: Test java/nio/channels/DatagramChannel/SendReceiveMaxSize.java timeout

[SendaoYan]

Hi,
On linux test environments which has docker service, `ifconfig` shows that `docker0` appears to be a virtual ethernet bridge which is created by the docker host. And the `docker0` virtual ethernet bridge may cause test `java/nio/channels/DatagramChannel/SendReceiveMaxSize.java` bind `docker0` ander network port. 
I think we should just skip "docker0" interfaces when looking for an IPv4 address for tests.
Change has been verified, test fix only, the risk is low.

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Commit messages:
 - 8338630: Test java/nio/channels/DatagramChannel/SendReceiveMaxSize.java timeout

Changes: https://git.openjdk.org/jdk/pull/20658/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20658&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8338630
  Stats: 8 lines in 1 file changed: 7 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/20658.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20658/head:pull/20658

PR: https://git.openjdk.org/jdk/pull/20658