Avoid deprecated field in Welcom page

Summary:

Test Plan:

Author: captbaritone

website/docs/01-getting-started/index.mdx

@@ -22,13 +22,6 @@ export function me(): User {
   return new User();
 }
 
-/**
- * @gqlQueryField
- * @deprecated Please use `me` instead. */
-export function viewer(): User {
-  return new User();
-}
-
 /**
  * A user in our kick-ass system!
  * @gqlType */
@@ -52,13 +45,6 @@ export function me(): User {
   return { name: "Alice" };
 }
 
-/**
- * @gqlQueryField
- * @deprecated Please use `me` instead.  */
-export function viewer(): User {
-  return { name: "Alice" };
-}
-
 /**
  * A user in our kick-ass system!
  * @gqlType */
@@ -83,7 +69,6 @@ Both of the above examples define the following GraphQL schema:
 ```graphql
 type Query {
   me: User
-  viewer: User @deprecated(reason: "Please use `me` instead.")
 }
 
 """