Revert the name of the SBT plugin beacon file at the CB

Author: anatoliykmetyuk

project/Build.scala

@@ -1184,7 +1184,7 @@ object Build {
       }.dependsOn(compile in Compile).evaluated
     )
 
-  val prepareCommunityBuild = taskKey[Unit]("Publish local the compiler and the sbt plugin. Also store the versions of the published local artefacts in two files, community-build/{scala3-bootstrapped.version,sbt-scala3-sbt}.")
+  val prepareCommunityBuild = taskKey[Unit]("Publish local the compiler and the sbt plugin. Also store the versions of the published local artefacts in two files, community-build/{scala3-bootstrapped.version,sbt-dotty-sbt}.")
 
   lazy val `community-build` = project.in(file("community-build")).
     dependsOn(dottyLibrary(Bootstrapped)).
@@ -1204,7 +1204,7 @@ object Build {
         val pluginText =
           s"""updateOptions in Global ~= (_.withLatestSnapshots(false))
              |addSbtPlugin("ch.epfl.lamp" % "sbt-dotty" % "$sbtDottyVersion")""".stripMargin
-        IO.write(baseDirectory.value / "sbt-scala3-sbt", pluginText)
+        IO.write(baseDirectory.value / "sbt-dotty-sbt", pluginText)
         IO.write(baseDirectory.value / "scala3-bootstrapped.version", dottyVersion)
       },
       testOptions in Test += Tests.Argument(