66075: Improvements from feedback:

- DspaceObjectMetadataOperation.performPatchOperation()
  > Logic split into seperate methods
- DspaceObjectMetadataOperation.replace()
  > Split into method per case

dspace-api/src/main/java/org/dspace/content/DSpaceObjectServiceImpl.java

@@ -756,4 +756,9 @@ public abstract class DSpaceObjectServiceImpl<T extends DSpaceObject> implements
         }
     }
 
+    @Override
+    public void setMetadataModified(T dso) {
+        dso.setMetadataModified();
+    }
+
 }