Set reference version to 3.3.1-RC3

Author: Kordyjan

project/Build.scala

@@ -83,7 +83,7 @@ object DottyJSPlugin extends AutoPlugin {
 object Build {
   import ScaladocConfigs._
 
-  val referenceVersion = "3.3.1-RC2"
+  val referenceVersion = "3.3.1-RC3"
 
   val baseVersion = "3.3.2-RC1" // temporarily, before branching out `3.4.0-RC1`