RFR: 8344188: Cleanup sun.net.www.protocol.jar.JarFileFactory after JEP 486 integration

[Eirik Bjørsnøs]

Please review this PR which removes SM permission checking from `s.n.w.p.j.JarFileFactory`.

This removes the permission checking happening in `JarFileFactory::getCachedJarFile` and also removes the associated private `getPermission` method, (sadly including the cute `// gulp`). The import of `java.security.Permission` is also removed.

Testing: `test/jdk/sun/net/www/protocol/jar` runs green, GHA results pending.

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Commit messages:
 - Remove SecurityManager permission checking from JarFileFactory

Changes: https://git.openjdk.org/jdk/pull/22135/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22135&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8344188
  Stats: 42 lines in 1 file changed: 0 ins; 41 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/22135.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22135/head:pull/22135

PR: https://git.openjdk.org/jdk/pull/22135