[jdk11u-dev] RFR: 8232625: HttpClient redirect policy should be more conservative

[Antonio Vieiro]

Clean backport of [JDK-8232625](https://bugs.openjdk.org/browse/JDK-8232625)  that improves HttpClient redirection by dropping the body when the HTTP request method changes.

Tested on linux with tier1 tests and the following:


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Test summary
==============================
   TEST                                              TOTAL  PASS  FAIL ERROR   
   jtreg:test/jdk/java/net/httpclient                  204   204     0     0   
==============================
TEST SUCCESS

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Commit messages:
 - Backport b3477399d01c81dfe87e2041926a0244e616c18f

Changes: https://git.openjdk.org/jdk11u-dev/pull/3030/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=3030&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8232625
  Stats: 514 lines in 5 files changed: 502 ins; 0 del; 12 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/3030.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/3030/head:pull/3030

PR: https://git.openjdk.org/jdk11u-dev/pull/3030