Skip distinct txn tests on 4.2 sharded clusters

Author: jyemin

driver-reactive-streams/src/test/functional/com/mongodb/reactivestreams/client/unified/UnifiedTransactionsTest.java

@@ -16,6 +16,7 @@
 
 package com.mongodb.reactivestreams.client.unified;
 
+import com.mongodb.ClusterFixture;
 import org.bson.BsonArray;
 import org.bson.BsonDocument;
 import org.junit.runners.Parameterized;
@@ -24,6 +25,8 @@
 import java.net.URISyntaxException;
 import java.util.Collection;
 
+import static com.mongodb.ClusterFixture.isSharded;
+import static com.mongodb.ClusterFixture.serverVersionLessThan;
 import static org.junit.Assume.assumeFalse;
 
 public class UnifiedTransactionsTest extends UnifiedReactiveStreamsTest {
@@ -33,6 +36,10 @@ public UnifiedTransactionsTest(@SuppressWarnings("unused") final String fileDesc
                                    final BsonArray initialData, final BsonDocument definition) {
         super(schemaVersion, runOnRequirements, entitiesArray, initialData, definition);
         assumeFalse(fileDescription.equals("count"));
+        if (serverVersionLessThan(4, 4) && isSharded()) {
+            assumeFalse(fileDescription.equals("pin-mongos") && testDescription.equals("distinct"));
+            assumeFalse(fileDescription.equals("read-concern") && testDescription.equals("only first distinct includes readConcern"));
+        }
     }
 
     @Parameterized.Parameters(name = "{0}: {1}")