[chore] Fix readme file for all-contributors

Author: BrainBuzzer

README.md

@@ -28,14 +28,17 @@ Currently supported PHP versions are:
 
 Feel free to open an issue or a pull request if you have any suggestions or bug reports.
 
-# Contributors
+## Contributors ✨
+
+Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/docs/en/emoji-key)):
 
 <!-- ALL-CONTRIBUTORS-LIST:START - Do not remove or modify this section -->
 <!-- prettier-ignore-start -->
 <!-- markdownlint-disable -->
 
 <!-- markdownlint-restore -->
 <!-- prettier-ignore-end -->
-
 <!-- ALL-CONTRIBUTORS-LIST:END -->
 
+This project follows the [all-contributors](https://github.com/all-contributors/all-contributors) specification. Contributions of any kind welcome!
+