RFR: JDK-8301306: java/net/httpclient/* fail with -Xcomp: java.io.IOException: HTTP/1.1 header parser received no bytes

[SUN Guoyun]

Hi all,
I think `BackgroundCompilation` should not be set to false when `-Xcomp` be used, which causes the java thread to block for longer, then causing the following tests failed frequently on the AArch64 and LoongArch64 architecture.

java/net/httpclient/ByteArrayPublishers.java （fastdebug -Xcomp）
java/net/httpclient/ManyRequestsLegacy.java （fastdebug -Xcomp）
java/net/httpclient/HttpClientLocalAddrTest.java （fastdebug -Xcomp）
jdk/incubator/concurrent/StructuredTaskScope/StructuredTaskScopeTest.java （fastdebug -Xcomp）
java/rmi/server/UnicastRemoteObject/serialFilter/FilterUROTest.java （release -Xcomp）

This PR delete BackgroundCompilation be setted, Above tests can be passed. Please help review it.

Thanks.

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Commit messages:
 - JDK-8301306: java/net/httpclient/* fail with -Xcomp: java.io.IOException: HTTP/1.1 header parser received no bytes

Changes: https://git.openjdk.org/jdk/pull/12282/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12282&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8301306
  Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/12282.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12282/head:pull/12282

PR: https://git.openjdk.org/jdk/pull/12282