RFR: 8217914: java/net/httpclient/ConnectTimeoutHandshakeSync.java failed on connection refused while doing POST

[Volkan Yazıcı]

Hardens `URI` build in `AbstractConnectTimeoutHandshake`, which is extended by both `ConnectTimeoutHandshakeSync` and `ConnectTimeoutHandshakeAsync`. (Will share `tier2` results when they complete.)

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Commit messages:
 - Harden `URI` build in `AbstractConnectTimeoutHandshake`

Changes: https://git.openjdk.org/jdk/pull/23162/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23162&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8217914
  Stats: 22 lines in 3 files changed: 11 ins; 6 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/23162.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23162/head:pull/23162

PR: https://git.openjdk.org/jdk/pull/23162