SOLR-13375 - fix test. Can't shuffle the to random collections at

this point in the test since the collections available are changing due
to deletions and we might try to communicate with a collection
that was (correctly) deleted.

(cherry picked from commit a7435d9e6e)

solr/core/src/test/org/apache/solr/update/processor/DimensionalRoutedAliasUpdateProcessorTest.java

@@ -560,7 +560,7 @@ public class DimensionalRoutedAliasUpdateProcessorTest extends RoutedAliasUpdate
         )
     );
 
-    addDocsAndCommit(false,
+    addDocsAndCommit(true,
         newDoc("shorthair", "2019-07-02T23:00:00Z"), // no effect expected
         newDoc("calico", "2019-07-06T00:00:00Z")     // create July 6, delete July 1
     );