chore: MiMa latest patch of 2.10 (akka#32876)

Author: sebastian-alfers

project/MiMa.scala

@@ -22,7 +22,7 @@ object MiMa extends AutoPlugin {
   private val firstPatchOf29 = 0
   private val latestPatchOf29 = 8
   private val firstPatchOf210 = 0
-  private val latestPatchOf210 = 14
+  private val latestPatchOf210 = 15
 
   override def requires = MimaPlugin
   override def trigger = allRequirements