HDDS-9434. Intermittent failure in TestSnapshotDiffManager#testLoadJobsOnStartUp.

[sadanand48]

What changes were proposed in this pull request?

Fix intermittent failure in the test by waiting till the method is invoked.

What is the link to the Apache JIRA

https://issues.apache.org/jira/browse/HDDS-9434

How was this patch tested?

Test successfully ran for 20 x 15 times : https://github.com/sadanand48/hadoop-ozone/actions/runs/6482699582

[kerneltime]

@swamirishi can you please take a look

[hemantk-12]

Thanks for the patch @sadanand48. Overall looks good to me.

Can you please run all the tests in TestSnapshotDiffManager 10x10 times instead of just testLoadJobsOnStartUp?

[sadanand48]

Thanks @hemantk-12 I ran all tests here : https://github.com/sadanand48/hadoop-ozone/actions/runs/6585565236/job/17892237098 .
There seems to be a failure in one case causing rocksdb crash , don't think it is related to this particular case but might be from other tests which is causing this

Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
C  0x00007f675c0007c0
C  [librocksdbjni3012275943445778470.so+0x2b30b2]  Java_org_rocksdb_RocksDB_get__J_3BIIJ+0x62
j  org.rocksdb.RocksDB.get(J[BIIJ)[B+0
J 6657 C1 org.apache.hadoop.ozone.om.snapshot.RocksDbPersistentMap.get(Ljava/lang/Object;)Ljava/lang/Object; (51 bytes) @ 0x00007f674d614bb4 [0x00007f674d614aa0+0x114]
j  org.apache.hadoop.ozone.om.snapshot.SnapshotDiffManager.areDiffJobAndSnapshotsActive(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)Z+215
v  ~StubRoutines::call_stub
V  [libjvm.so+0x69f2f2]  JavaCalls::call_helper(JavaValue*, methodHandle*, JavaCallArguments*, Thread*)+0xe32
V  [libjvm.so+0x9f4d90]  Reflection::invoke(instanceKlassHandle, methodHandle, Handle, bool, objArrayHandle, BasicType, objArrayHandle, bool, Thread*)+0xb10
V  [libjvm.so+0x9f6866]  Reflection::invoke_method(oopDesc*, Handle, objArrayHandle, Thread*)+0x126
V  [libjvm.so+0x74bb05]  JVM_InvokeMethod+0x115
J 2708  sun.reflect.NativeMethodAccessorImpl.invoke0(Ljava/lang/reflect/Method;Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object; (0 bytes) @ 0x00007f674d6ffe2d [0x00007f674d6ffd40+0xed]
J 2707 C1 sun.reflect.NativeMethodAccessorImpl```

[adoroszlai]

Thanks @sadanand48 for the patch, @hemantk-12 for the review.