Update src/Map/tests/Cluster/GridClusteringAlgorithmTest.php

Co-authored-by: Hugo Alliaume <hugo@alliau.me>

Author: smnandre

src/Map/tests/Cluster/GridClusteringAlgorithmTest.php

@@ -40,10 +40,9 @@ public function testPointsInSameGridAreClusteredTogether(): void
         $point2 = new Point(10.1, 20.1);
         $algorithm = new GridClusteringAlgorithm();
 
-        // Low zoom
         $clusters = $algorithm->cluster([$point1, $point2], 1.0);
 
-        $this->assertCount(1, $clusters);
+        $this->assertCount(1, $clusters, 'One cluster should have been created due to the low zoom value.');
 
         $cluster = $clusters[0];