Update scala-library to 2.12.20 in Atry-patch-1

Author: Atry

.github/workflows/scala.yml

@@ -16,7 +16,7 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - scala: 2.12.13
+          - scala: 2.12.20
             sbt-args: --addPluginSbtFile=project/plugins.sbt.scalajs06
           - scala: 2.13.4
             sbt-args: --addPluginSbtFile=project/plugins.sbt.scalajs06