Use released version.

tarao · tarao · commit f5fad99cd88a · 2022-10-11T14:27:19.000+09:00
diff --git a/build.sbt b/build.sbt
@@ -1,4 +1,4 @@
-val scala3Version = "3.1.2-RC1"
+val scala3Version = "3.1.2"
 
 lazy val root = project
   .in(file("."))
