Improved ConnectionTest performance

Methods testMastersShuffled and testMastersSequential executed about 30 seconds each.
This commit reduces execution time to 2-5 seconds each.

tests/framework/db/sqlite/ConnectionTest.php

@@ -117,6 +117,9 @@ class ConnectionTest extends \yiiunit\framework\db\ConnectionTest
 
             $hit_slaves[$db->getSlave()->dsn] = true;
             $hit_masters[$db->getMaster()->dsn] = true;
+            if (count($hit_slaves) === $slavesCount && count($hit_masters) === $mastersCount) {
+                break;
+            }
         }
 
         $this->assertCount($mastersCount, $hit_masters, 'all masters hit');
@@ -139,6 +142,9 @@ class ConnectionTest extends \yiiunit\framework\db\ConnectionTest
 
             $hit_slaves[$db->getSlave()->dsn] = true;
             $hit_masters[$db->getMaster()->dsn] = true;
+            if (count($hit_slaves) === $slavesCount) {
+                break;
+            }
         }
 
         $this->assertCount(1, $hit_masters, 'same master hit');