Update scala-library to 2.12.20

Author: scala-steward

build.sbt

@@ -5,8 +5,8 @@ import java.net.URI
 lazy val compileScalastyle = taskKey[Unit]("compileScalastyle")
 
 val commonSettings = Seq(
-  ThisBuild / scalaVersion := "2.12.19",
-  crossScalaVersions := Seq("2.12.19", "2.13.14", "3.3.3"),
+  ThisBuild / scalaVersion := "2.12.20",
+  crossScalaVersions := Seq("2.12.20", "2.13.14", "3.3.3"),
 
   ThisBuild / parallelExecution := false,
   fork := true,