Update sbt-coursier, sbt-shading to 2.0.0-RC4-1 (#127)

Author: scala-steward

project/plugins.sbt

@@ -2,5 +2,5 @@ addSbtPlugin("com.geirsson" % "sbt-ci-release" % "1.4.31")
 addSbtPlugin("org.scala-js" % "sbt-scalajs" % "0.6.29")
 addSbtPlugin("org.portable-scala" % "sbt-scalajs-crossproject" % "0.6.1")
 addSbtPlugin("com.typesafe" % "sbt-mima-plugin" % "0.6.1")
-addSbtPlugin("io.get-coursier" % "sbt-coursier" % "2.0.0-RC4")
-addSbtPlugin("io.get-coursier" % "sbt-shading" % "2.0.0-RC4")
+addSbtPlugin("io.get-coursier" % "sbt-coursier" % "2.0.0-RC4-1")
+addSbtPlugin("io.get-coursier" % "sbt-shading" % "2.0.0-RC4-1")