[jdk11u-dev] RFR: 8242044: Add basic HTTP/1.1 support to the HTTP/2 Test Server

[Goetz Lindenmaier]

I downport this for parity with 11.0.13-oracle.

I had to change jdk.test.lib.net.SimpleSSLContext to jdk.testlibrary.SimpleSSLContext and add the according @library.
Else the test does not compile.
Test is passing.

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Commit messages:
 - Backport 9a69bb807beb6693c68a7b11bee435c0bab7ceac

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/397/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=397&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8242044
  Stats: 337 lines in 3 files changed: 319 ins; 3 del; 15 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/397.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/397/head:pull/397

PR: https://git.openjdk.java.net/jdk11u-dev/pull/397