RFR: 8300172: java/net/httpclient/MappingResponseSubscriber.java failed with java.net.ConnectException

[Daniel Fuchs]

The MappingResponseSubscriber test has been observed failing on windows in our CI due to a ConnectException.
I am suspecting that some kind of connection limit enforced by the system has been reached.
We can see from the log that the TCP connection has failed, been retried, and failed again.
Previous connections to the same server seem to have succeeded.

Modifying the test to wait after previous clients have been GC'ed before opening the next one could alleviate the situation.

-------------

Commit messages:
 - 8300172

Changes: https://git.openjdk.org/jdk/pull/12013/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12013&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8300172
  Stats: 28 lines in 1 file changed: 20 ins; 0 del; 8 mod
  Patch: https://git.openjdk.org/jdk/pull/12013.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12013/head:pull/12013

PR: https://git.openjdk.org/jdk/pull/12013