Update docs to refer to the new Scala 3 gitter8

Author: soronpo

docs/index.html

@@ -85,7 +85,7 @@ <h1 id="getting-started-with-a-project">Create a Scala 3 Project</h1>
       <p>The fastest way to create a new project in Scala 3 is using <a href="http://www.scala-sbt.org/">sbt (1.1.4+)</a>.</p>
 
       <p>Create a Scala 3 project:</p>
-      <pre><code>sbt new <a href="https://github.com/lampepfl/dotty.g8">lampepfl/dotty.g8</a></code></pre>
+      <pre><code>sbt new <a href="https://github.com/scala/scala3.g8">scala/scala3.g8</a></code></pre>
 
       <p>Or a Scala 3 project that cross compiles with Scala 2:</p>
       <pre><code>sbt new <a href="https://github.com/lampepfl/dotty-cross.g8">lampepfl/dotty-cross.g8</a></code></pre>