linstor unit test fix

Author: sureshanaparti

plugins/storage/volume/linstor/src/test/java/org/apache/cloudstack/storage/motion/LinstorDataMotionStrategyTest.java

@@ -169,6 +169,7 @@ public void setUp() throws Exception {
         when(srcVolumeInfo.getPath()).thenReturn("216fb792-c5ed-4ad7-98e6-ebdd25816e55");
         when(srcVolumeInfo.getDataStore()).thenReturn(srcDataStore);
         when(srcVolumeInfo.getPassphraseId()).thenReturn(null);
+        when(srcVolumeInfo.getKmsKeyId()).thenReturn(null);
         StoragePoolVO srcPool = mock(StoragePoolVO.class);
         when(srcPool.getPoolType()).thenReturn(Storage.StoragePoolType.NetworkFilesystem);
         when(_storagePool.findById(SRC_POOL_ID)).thenReturn(srcPool);