JVMCBC-1662 Preferred server group not honored in transactions

Motivation
----------
Honor the "preferredServerGroup" option for replica
reads in transactions.

Modifications
-------------
Update NodeIndexCalculator to treat
PREFERRED_SERVER_GROUP_OR_ALL_AVAILABLE
the same as PREFERRED_SERVER_GROUP.

The collaborator (ReplicaHelper) already handles
falling back to all replicas if none are available
in the preferred group.

Change-Id: I051dcf72b06a4f345aa428327acb295a3bee43c6
Reviewed-on: https://review.couchbase.org/c/couchbase-jvm-clients/+/229517
Tested-by: Build Bot <[email protected]>
Reviewed-by: Michael Reiche <[email protected]>

Author: dnault

core-io/src/main/java/com/couchbase/client/core/service/kv/NodeIndexCalculator.java

@@ -25,6 +25,8 @@
 
 import java.nio.charset.StandardCharsets;
 
+import static com.couchbase.client.core.api.kv.CoreReadPreference.PREFERRED_SERVER_GROUP;
+import static com.couchbase.client.core.api.kv.CoreReadPreference.PREFERRED_SERVER_GROUP_OR_ALL_AVAILABLE;
 import static com.couchbase.client.core.node.KeyValueLocator.partitionForKey;
 
 @Stability.Internal
@@ -40,7 +42,7 @@ public NodeIndexCalculator(CoreReadPreference readPreference, CouchbaseBucketCon
       boolean canUseNode = true;
       PortInfo node = topology.portInfos().get(nodeIndex);
 
-      if (readPreference == CoreReadPreference.PREFERRED_SERVER_GROUP) {
+      if (readPreference == PREFERRED_SERVER_GROUP || readPreference == PREFERRED_SERVER_GROUP_OR_ALL_AVAILABLE) {
         canUseNode = node.serverGroup() != null && node.serverGroup().equals(coreContext.environment().preferredServerGroup());
       }