Update integration tests to account for new explain command reply format (#716)

JAVA-4169

Author: jyemin

driver-core/src/test/functional/com/mongodb/internal/operation/QueryOperationHelper.groovy

@@ -32,7 +32,12 @@ class QueryOperationHelper {
 
     static BsonDocument getKeyPattern(BsonDocument explainPlan) {
         BsonDocument winningPlan = explainPlan.getDocument('queryPlanner').getDocument('winningPlan')
-        if (winningPlan.containsKey('inputStage')) {
+        if (winningPlan.containsKey('queryPlan')) {
+            BsonDocument queryPlan = winningPlan.getDocument('queryPlan')
+            if (queryPlan.containsKey('inputStage')) {
+                return queryPlan.getDocument('inputStage').getDocument('keyPattern')
+            }
+        } else if (winningPlan.containsKey('inputStage')) {
             return winningPlan.getDocument('inputStage').getDocument('keyPattern')
         } else if (winningPlan.containsKey('shards')) {
             return winningPlan.getArray('shards')[0].asDocument().getDocument('winningPlan')

driver-legacy/src/test/functional/com/mongodb/DBCursorFunctionalSpecification.groovy

@@ -269,7 +269,9 @@ class DBCursorFunctionalSpecification extends FunctionalSpecification {
     def caseInsensitiveCollation = Collation.builder().locale('en').collationStrength(CollationStrength.SECONDARY).build()
 
     static DBObject getKeyPattern(DBObject explainPlan) {
-        if (explainPlan.queryPlanner.winningPlan.inputStage != null) {
+        if (explainPlan.queryPlanner.winningPlan.queryPlan?.inputStage != null) {
+            return explainPlan.queryPlanner.winningPlan.queryPlan.inputStage.keyPattern
+        } else if (explainPlan.queryPlanner.winningPlan.inputStage != null) {
             return explainPlan.queryPlanner.winningPlan.inputStage.keyPattern
         } else if (explainPlan.queryPlanner.winningPlan.shards != null) {
             return explainPlan.queryPlanner.winningPlan.shards[0].winningPlan.inputStage.keyPattern