use discord.com links not discord.gg

Author: SethTisue

_data/chats-forums.yml

@@ -10,7 +10,7 @@ discourseForums:
 
 discordServers:
   - name: Scala
-    url: https://discord.gg/scala
+    url: https://discord.com/invite/scala
   - name: Scalameta
     url: https://discord.gg/RFpSVth
   - name: Typelevel

_data/footer.yml

@@ -53,6 +53,6 @@
     - title: Twitter
       url: "https://twitter.com/scala_lang"
     - title: Discord
-      url: "https://discord.gg/scala"
+      url: "https://discord.com/invite/scala"
     - title: LinkedIn
       url: "https://www.linkedin.com/company/scala-center/"

community/index.md

@@ -57,7 +57,7 @@ Job postings are not allowed in our other forums and chat rooms.
 
 Our main chat platform is Discord, and the main Scala server is:
 
-* **[Scala](https://discord.gg/scala)**
+* **[Scala](https://discord.com/invite/scala)**
   * the #scala-users channel is especially beginner-friendly
   * the #scala-contributors channel is about moving Scala forward
   * the #jobs channel is the only place we allow job postings