[SLC] AbstractSymbolLightClassesByPsiTest: add more stable order

Now more diff between sources and libraries are readable.
Also prefer .descriptors to .fir as FIR is a first-class support

^KT-62892

compiler/testData/asJava/lightClasses/lightClassByPsi/dollarsInNameLocal.descriptors.java

@@ -0,0 +1,27 @@
+public final class $$$$$$$ /* null*/ {
+  public  $$$$$$$();//  .ctor()
+
+  class G$G$ ...
+}
+
+public static final class A$B /* null*/ {
+  public  A$B();//  .ctor()
+
+  class $$$$$$$ ...
+
+  class C$D ...
+}
+
+public final class C$D /* null*/ {
+  public  C$D();//  .ctor()
+}
+
+public final class Foo /* c.b.a.Foo*/ {
+  public  Foo();//  .ctor()
+
+  public final void bar();//  bar()
+}
+
+public final class G$G$ /* null*/ {
+  public  G$G$();//  .ctor()
+}