Show that we support runtime 5.3 (#40)

Nyholm · web-flow · commit 58c522ce26ce · 2021-04-29T10:57:08.000+02:00
diff --git a/composer.json b/composer.json
@@ -10,7 +10,7 @@
         }
     ],
     "require": {
-        "symfony/runtime": "5.x-dev"
+        "symfony/runtime": "^5.3"
     },
     "require-dev": {
         "swoole/ide-helper": "^4.6",
