[jdk17u-dev] RFR: 8304962: sun/net/www/http/KeepAliveCache/B5045306.java: java.lang.RuntimeException: Failed: Initial Keep Alive Connection is not being reused

[Amos Shi]

Backport of [JDK-8304962](https://bugs.openjdk.org/browse/JDK-8304962)

Testing
- Local: Test passed
  - `B5045306.java`: Test results: passed: 1
- Pipeline: 
- Testing Machine:

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Commit messages:
 - Backport cddaf686e16424e9543be50a48b1c02337e79cf1

Changes: https://git.openjdk.org/jdk17u-dev/pull/2772/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2772&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8304962
  Stats: 9 lines in 1 file changed: 1 ins; 2 del; 6 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2772.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2772/head:pull/2772

PR: https://git.openjdk.org/jdk17u-dev/pull/2772