fixed small comments on PR

receiver/mongodbreceiver/client_test.go

@@ -74,7 +74,16 @@ func (fc *fakeClient) RunCommand(ctx context.Context, db string, command bson.M)
 	if args.Get(0) == nil {
 		return nil, args.Error(1)
 	}
-	return args.Get(0).(bson.M), args.Error(1)
+
+	result, ok := args.Get(0).(bson.M)
+	if !ok {
+		err := errors.New("mock returned invalid type")
+		zap.L().Error("type assertion failed",
+			zap.String("expected", "bson.M"))
+		return nil, err
+	}
+
+	return result, args.Error(1)
 }
 
 func TestListDatabaseNames(t *testing.T) {

receiver/mongodbreceiver/scraper.go

@@ -304,7 +304,7 @@ func (s *mongodbScraper) findSecondaryHosts(ctx context.Context) ([]string, erro
 
 	members, ok := result["members"].(primitive.A)
 	if !ok {
-		return nil, fmt.Errorf("invalid members format")
+		return nil, fmt.Errorf("invalid members format: expected type primitive.A but got %T, value: %v", result["members"], result["members"])
 	}
 
 	var hosts []string
@@ -333,9 +333,5 @@ func (s *mongodbScraper) findSecondaryHosts(ctx context.Context) ([]string, erro
 		}
 	}
 
-	if len(hosts) == 0 {
-		s.logger.Warn("No secondary hosts found in replica set")
-	}
-
 	return hosts, nil
 }

receiver/mongodbreceiver/testdata/integration/expected.4_4lpu.yaml

@@ -136,7 +136,7 @@ resourceMetrics:
                   startTimeUnixNano: "1682363202250964000"
                   timeUnixNano: "1682363222253814000"
               isMonotonic: true
-            unit: '{operations}'                                       
+            unit: '{operations}'
           - description: The total time spent performing operations.
             name: mongodb.operation.time
             sum: