Fix migration PHP file detection

Author: lcharette

app/sprinkles/core/src/Database/Migrator/MigrationLocator.php

@@ -56,7 +56,7 @@ public function getMigrations()
         foreach ($migrationFiles as $migrationFile) {
             // Note that PSR4 insists that all php files must end in PHP, so ignore all
             // files that don't end in PHP.
-            if (preg_match('/php$/', $migrationFile)) {
+            if ($migrationFile->getExtension() == 'php') {
                 $migrations[] = $this->getMigrationDetails($migrationFile);
             }
         }

app/sprinkles/core/tests/Integration/Database/Migrator/MigrationLocatorTest.php

@@ -90,7 +90,13 @@ public function testGetMigrations()
             new Resource($resourceStream, $resourceAccountLocation, 'one/CreatePasswordResetsTable.php'),
             new Resource($resourceStream, $resourceAccountLocation, 'two/CreateFlightsTable.php'),
             new Resource($resourceStream, $resourceAccountLocation, 'CreateMainTable.php'),
-            new Resource($resourceStream, $resourceAccountLocation, 'README.md'), // This shoudn't be returned by the migrator
+
+            // Theses shoudn't be returned by the migrator
+            new Resource($resourceStream, $resourceAccountLocation, 'README.md'),
+            new Resource($resourceStream, $resourceAccountLocation, 'php.md'),
+            new Resource($resourceStream, $resourceAccountLocation, 'foo.foophp'),
+            new Resource($resourceStream, $resourceAccountLocation, 'blah.phpphp'),
+            new Resource($resourceStream, $resourceAccountLocation, 'bar.phpbar'),
         ]);
 
         // Create a new MigrationLocator instance with our simulated ResourceLocation