Rely on a version for CmfTesting

Author: wouterj

composer.json

@@ -19,7 +19,7 @@
         "psr/log": "1.*"
     },
     "require-dev": {
-        "symfony-cmf/testing": "dev-sf_3.0",
+        "symfony-cmf/testing": "^1.3",
         "symfony/dependency-injection": "^2.0.5|3.*",
         "symfony/config": "^2.2|3.*",
         "symfony/event-dispatcher": "^2.1|3.*"