drop MiMa against LTS. It was never checked...

[Cherry-picked 05d0798][modified]

Author: WojciechMazur

project/Build.scala

@@ -134,14 +134,6 @@ object Build {
    */
   val mimaPreviousDottyVersion = "3.7.3" // for 3.8.0, we compare against 3.7.3
 
-  /** LTS version against which we check binary compatibility.
-   *
-   *  This must be the earliest published release in the LTS versioning line.
-   *  For example, if the latest LTS release is be 3.3.4, then this must be
-   *  set to 3.3.0.
-   */
-  val mimaPreviousLTSDottyVersion = "3.3.0"
-
   /** Version of Scala CLI to download */
   val scalaCliLauncherVersion = "1.10.1"
   /** Version of Coursier to download for initializing the local maven repo of Scala command */

project/MiMaFilters.scala

@@ -497,6 +497,21 @@ object MiMaFilters {
     )
   }
 
+  object ScalaLibrarySJS {
+    val ForwardsBreakingChanges: Map[String, Seq[ProblemFilter]] = Map(
+      // Additions that require a new minor version of the library
+      Build.mimaPreviousDottyVersion -> Seq(
+        // No .class files generated in the artifacts, only `scala.scalajs.*` files might be present
+        ProblemFilters.exclude[MissingClassProblem]("scala.*"),
+      ),
+    )
+
+    val BackwardsBreakingChanges: Map[String, Seq[ProblemFilter]] = Map(
+      // We should never break backwards compatibility
+      Build.mimaPreviousDottyVersion -> Seq.empty,
+    )
+  }
+
   object TastyCore {
     val ForwardsBreakingChanges: Map[String, Seq[ProblemFilter]] = Map(
       // Additions that require a new minor version of tasty core