RFR: 8305095: Update java/net/httpclient/CustomRequestPublisher.java to use new HttpTestServer factory methods [v2]

[Daniel Fuchs]

> Please find here a trivial change that upgrades the CustomRequestPublisher test to use the new HttpTestServer factory methods.

Daniel Fuchs has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:

 - Merge branch 'master' into CustomRequestPublisher-8305095
 - Removed unused imports
 - 8305095

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Changes:
  - all: https://git.openjdk.org/jdk/pull/13211/files
  - new: https://git.openjdk.org/jdk/pull/13211/files/5c6cd8f4..9f1e8174

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13211&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13211&range=00-01

  Stats: 541 lines in 5 files changed: 224 ins; 192 del; 125 mod
  Patch: https://git.openjdk.org/jdk/pull/13211.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13211/head:pull/13211

PR: https://git.openjdk.org/jdk/pull/13211