Fix isJvmAccessible returns true if the protected class is accessible

fix #24507

but I'm concerned about the comment

> // We can't rely on `isContainedWith` here because packages are
> // not nested from the JVM point of view.

Author: tanishiking

compiler/src/dotty/tools/dotc/transform/Erasure.scala

@@ -753,7 +753,8 @@ object Erasure {
           // not nested from the JVM point of view.
           val boundary = cls.accessBoundary(cls.owner)(using preErasureCtx)
           (boundary eq defn.RootClass) ||
-          (ctx.owner.enclosingPackageClass eq boundary)
+          (ctx.owner.enclosingPackageClass eq boundary) ||
+          (cls.is(Flags.Protected) && cls.isAccessibleFrom(ctx.owner.enclosingClass.thisType)(using preErasureCtx))
         }
 
       @tailrec

tests/pos/i24507.scala

@@ -0,0 +1,2 @@
+class Test extends javax.swing.JFrame { class Acc extends AccessibleJFrame }
+