RFR: 8359223: HttpClient: Remove leftovers from the SecurityManager cleanup

[Volkan Yazici]

Removes following files added in [JDK-8235459](https://bugs.openjdk.org/browse/JDK-8235459) and are forgotten to be removed during the `SecurityManager`-removal ([JDK-8344228](https://bugs.openjdk.org/browse/JDK-8344228)):


test/jdk/java/net/httpclient/FilePublisher/FilePublisherPermsTest.java
test/jdk/java/net/httpclient/FilePublisher/SecureZipFSProvider.java

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Commit messages:
 - Remove leftover tests from the SecurityManager cleanup

Changes: https://git.openjdk.org/jdk/pull/25747/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25747&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8359223
  Stats: 701 lines in 2 files changed: 0 ins; 701 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/25747.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25747/head:pull/25747

PR: https://git.openjdk.org/jdk/pull/25747