Merge branch '5.3' into 5.4

* 5.3:
  Fix CS in README files
  Fix markdown
  [HttpKernel] Fixes tests for PHP7.4+
  [Filesystem] fix readlink for Windows

Author: nicolas-grekas

README.md

@@ -19,7 +19,7 @@ See your account info at https://gatewayapi.com
 Resources
 ---------
 
-  * [Contributing](https://symfony.com/doc/current/contributing/index.html)
-  * [Report issues](https://github.com/symfony/symfony/issues) and
-    [send Pull Requests](https://github.com/symfony/symfony/pulls)
-    in the [main Symfony repository](https://github.com/symfony/symfony)
+ * [Contributing](https://symfony.com/doc/current/contributing/index.html)
+ * [Report issues](https://github.com/symfony/symfony/issues) and
+   [send Pull Requests](https://github.com/symfony/symfony/pulls)
+   in the [main Symfony repository](https://github.com/symfony/symfony)