Merge pull request #8229 from dotty-staging/scalajs-1.0.0

Upgrade to Scala.js 1.0.0.

Author: smarter

project/plugins.sbt

@@ -2,10 +2,7 @@
 //
 // e.g. addSbtPlugin("com.github.mpeltonen" % "sbt-idea" % "1.1.0")
 
-// DO NOT update this plugin without regenerating our Docker
-// image (https://github.com/lampepfl/dotty-drone) or fixing
-// https://github.com/lampepfl/dotty/issues/3146.
-addSbtPlugin("org.scala-js" % "sbt-scalajs" % "1.0.0-RC2")
+addSbtPlugin("org.scala-js" % "sbt-scalajs" % "1.0.0")
 
 addSbtPlugin("org.xerial.sbt" % "sbt-sonatype" % "3.6")