CompressedClassSpaceSizeInJmapHeap.java time out after 8 minutes

[Note: if you are getting a test task timeout, usually after 4 hours, please file under JDK-8298073. This CR is for the test timing out, usually after about 8 minutes, but the test log saying that it also passed.]

The following test failed in the JDK15 CI:

gc/metaspace/CompressedClassSpaceSizeInJmapHeap.java

Here's a snippet from the log:

#section:main
----------messages:(7/536)----------
command: main -XX:+IgnoreUnrecognizedVMOptions -XX:CompressedClassSpaceSize=50m gc.metaspace.CompressedClassSpaceSizeInJmapHeap
reason: User specified action: run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:CompressedClassSpaceSize=50m gc.metaspace.CompressedClassSpaceSizeInJmapHeap
Mode: othervm [/othervm specified]
Additional options from @modules: --add-modules java.base,java.management --add-exports java.base/jdk.internal.misc=ALL-UNNAMED
Timeout information:
--- Timeout information end.
elapsed time (seconds): 492.208
----------configuration:(4/111)----------
Boot Layer
  add modules: java.base java.management
  add exports: java.base/jdk.internal.misc ALL-UNNAMED

----------System.out:(2/62)----------
Adding 'sudo -E -n' to the command.
Timeout refired 480 times
----------System.err:(1/15)----------
STATUS:Passed.
----------rerun:(36/5829)*----------
<snip>
result: Error. Program `/mesos/work_dir/jib-master/install/jdk-15+15-620/macosx-x64-debug.jdk/jdk-15/fastdebug/bin/java' timed out (timeout set to 480000ms, elapsed time including timeout handling was 492199ms).


test result: Error. Program `/mesos/work_dir/jib-master/install/jdk-15+15-620/macosx-x64-debug.jdk/jdk-15/fastdebug/bin/java' timed out (timeout set to 480000ms, elapsed time including timeout handling was 492199ms).


Please notice that the test passed during timeout handling:

> STATUS:Passed.

This test run is executing with debug bits. Perhaps this test
needs a slightly longer timeout value instead of the default
2 minutes/120 seconds. With the default timeout factor of 4,
that gives us a total timeout value of 8 minutes/480 seconds.

Bumping the timeout values to 180 will get us to a total timeout
value of 12 minutes/720 seconds.