Remove the JVM flags -XX:PermSize and -XX:MaxPermSize

More information: []

Tested:
    TAP for global presubmit queue
    []

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=189280946

java/com/google/testing/builddefs/GenTestRules.bzl

@@ -34,7 +34,7 @@ def GenTestRules(name,
                  flaky_tests=[],
                  tags=[],
                  prefix="",
-                 jvm_flags=["-XX:MaxPermSize=128m"],
+                 jvm_flags=[],
                  args=[],
                  visibility=None,
                  shard_count=1):