Update scala to 2.12.6

Philippus · Philippus · commit 49284d50eaac · 2018-05-02T15:10:35.000+02:00
diff --git a/build.sbt b/build.sbt
@@ -2,7 +2,7 @@ import ScalaModulePlugin._
 
 scalaVersionsByJvm in ThisBuild := {
   val v211 = "2.11.12"
-  val v212 = "2.12.4"
+  val v212 = "2.12.6"
   val v213 = "2.13.0-M3"
 
   Map(
