[NO ISSUE][COMP] Minor MetadataProvider refactoring

- user model changes: no
- storage format changes: no
- interface changes: no

Details:
- Add MetadataProvider.findSynonym() method

Change-Id: Idc7e0fa83da05b2892acbd786154acea7f2f4cd0
Reviewed-on: https://asterix-gerrit.ics.uci.edu/c/asterixdb/+/4703
Contrib: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Integration-Tests: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Dmitry Lychagin <dmitry.lychagin@couchbase.com>
Reviewed-by: Ali Alsuliman <ali.al.solaiman@gmail.com>
diff --git a/asterixdb/asterix-metadata/src/main/java/org/apache/asterix/metadata/declared/MetadataProvider.java b/asterixdb/asterix-metadata/src/main/java/org/apache/asterix/metadata/declared/MetadataProvider.java
index 55df495..1ee59bf 100644
--- a/asterixdb/asterix-metadata/src/main/java/org/apache/asterix/metadata/declared/MetadataProvider.java
+++ b/asterixdb/asterix-metadata/src/main/java/org/apache/asterix/metadata/declared/MetadataProvider.java
@@ -420,7 +420,7 @@
             return null;
         }
         while (MetadataManagerUtil.findDataset(mdTxnCtx, dvName, datasetName) == null) {
-            Synonym synonym = MetadataManagerUtil.findSynonym(mdTxnCtx, dvName, datasetName);
+            Synonym synonym = findSynonym(dvName, datasetName);
             if (synonym == null) {
                 return null;
             }
@@ -430,6 +430,10 @@
         return new Pair<>(dvName, datasetName);
     }
 
+    public Synonym findSynonym(DataverseName dataverseName, String synonymName) throws AlgebricksException {
+        return MetadataManagerUtil.findSynonym(mdTxnCtx, dataverseName, synonymName);
+    }
+
     @Override
     public IFunctionInfo lookupFunction(FunctionIdentifier fid) {
         return BuiltinFunctions.lookupFunction(fid);