Revert erronous tasty version change

Author: Kordyjan

tasty/src/dotty/tools/tasty/TastyFormat.scala

@@ -288,7 +288,7 @@ object TastyFormat {
    *  compatibility, but remains backwards compatible, with all
    *  preceeding `MinorVersion`.
    */
-  final val MinorVersion: Int = 2
+  final val MinorVersion: Int = 3
 
   /** Natural Number. The `ExperimentalVersion` allows for
    *  experimentation with changes to TASTy without committing