docs: change README contributions section

KoLiBer · KoLiBer · commit 3f13cbc23feb · 2020-09-23T10:28:34.000+03:30
diff --git a/README.md b/README.md
@@ -58,7 +58,7 @@ export class UserRepository extends FilterRepositoryMixin<
 
 ---
 
-## Contributions
+## Contributors
 
 -   [KoLiBer](https://www.linkedin.com/in/mohammad-hosein-nemati-665b1813b/)
 
