[chore] Set reference compiler to 3.10.0-RC1 (#26934)

Sets the reference compiler and mimaPreviousVersion to 3.10.0-RC1

Author: WojciechMazur

project/MiMaFilters.scala

@@ -4,6 +4,10 @@ import com.typesafe.tools.mima.core._
 
 object MiMaFilters {
 
+  // By default, you should include new filters under Versions.mimaPreviousVersion
+  // MiMa does collect all filters based on semantic versioning, so we don't need to duplicate them for each version
+  // Entries in mimaPreviousVersion would be moved to mimaPreviousLTSVersion or it's own dedicated version when new minor version is released
+
   object ScalaLibrary {
 
     val ForwardsBreakingChanges: Map[String, Seq[ProblemFilter]] = Map(
@@ -668,11 +672,11 @@ object MiMaFilters {
       Versions.mimaPreviousVersion -> Seq.empty,
 
       // Additions since last LTS
-      Versions.mimaPreviousLTSVersion -> Seq(
+      Versions.mimaPreviousLTSVersion -> Seq.empty,
+    ).mapValues(_ ++ 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

project/Versions.scala

@@ -12,7 +12,7 @@ object Versions {
    *
    *  Warning: Change of this variable needs to be consulted with `expectedTastyVersion`
    */
-  val referenceVersion = "3.9.0"
+  val referenceVersion = "3.10.0-RC1"
 
   /** Version of the Scala compiler targeted in the current release cycle
    *  Contains a version without RC/SNAPSHOT/NIGHTLY specific suffixes
@@ -87,7 +87,7 @@ object Versions {
    *   - `3.M.0`     if `P > 0`
    *   - `3.(M-1).0` if `P = 0`
    */
-  val mimaPreviousVersion = "3.9.0" // TODO: update to 3.10.0 when released
+  val mimaPreviousVersion = "3.10.0-RC1" // TODO: update to 3.10.0 when released
 
   /** LTS version against which we check binary compatibility.
    *