Light analysis tests: do not render empty lines between classes and in the beginning

compiler/testData/codegen/light-analysis/classes/implementComparableInSubclass.txt

@@ -4,7 +4,6 @@ public abstract class foo/Base {
     public final method getX(): int
 }
 
-
 public final class foo/Derived {
     private final field y: int
     public method <init>(): void
@@ -13,7 +12,6 @@ public final class foo/Derived {
     public final method getY(): int
 }
 
-
 public final class foo/ImplementComparableInSubclassKt {
     public final static @org.jetbrains.annotations.NotNull method box(): java.lang.String
 }