Fix grammatical error (#13249)

* Fix grammatical error

* Update contributors.yml

Author: samimsu

contributors.yml

@@ -368,3 +368,4 @@
 - yuleicul
 - zeromask1337
 - zheng-chuang
+- samimsu

docs/start/modes.md

@@ -95,7 +95,7 @@ Every mode supports any architecture and deployment target, so the question isn'
 
 **Use Declarative Mode if you:**
 
-- want to use React Router as a simply as possible
+- want to use React Router as simply as possible
 - are coming from v6 and are happy with the `<BrowserRouter>`
 - have a data layer that either skips pending states (like local first, background data replication/sync) or has its own abstractions for them
 - are coming from Create React App (you may want to consider framework mode though)