docs(readme): added cotributer charts

Author: remsky

README.md

@@ -661,3 +661,15 @@ This project is licensed under the Apache License 2.0 - see below for details:
 
 The full Apache 2.0 license text can be found at: https://www.apache.org/licenses/LICENSE-2.0
 </details>
+
+</details open>
+
+## Contributor Stats
+![Alt](https://repobeats.axiom.co/api/embed/f9694366bf96febc749d592316ff0a275fe77219.svg "Repobeats analytics image")
+</details>
+
+<a href="https://github.com/remsky/Kokoro-FastAPI/graphs/contributors">
+  <img src="https://contrib.rocks/image?repo=remsky/Kokoro-FastAPI" />
+</a>
+
+Made with [contrib.rocks](https://contrib.rocks).