Fixup class names in class decorator private identifier tests.

For the statement level test, the inner class name is not initialized
at the time the decorators evaluate, resulting in a ReferenceError
that the declaration can not be accessed prior to initialization.

Similar, non-decorator code, like:
    class C {
        static dec() {}
        static {
            this.x = C.dec();
            class C {}
        }
    }
also results in a ReferenceError.

For the expression level test, the var C is undefined at the time the
decorators are evaluated, resulting in TypeError while trying to access
a member of undefined.

Similar, non-decorator code, like:
    var C = class {
        static f() {};
        static {
            this.x = C.f();
        }
    }
also results in a TypeError.

test/language/expressions/class/decorator/syntax/class-valid/decorator-member-expr-private-identifier.js

@@ -32,7 +32,7 @@ info: |
 ---*/
 
 
-var C = class {
+class C {
   static #$() {}
   static #_() {}
   static #\u{6F}() {}
@@ -43,7 +43,7 @@ var C = class {
   static #await() {}
 
   static {
-    var C = @C.#$
+    var D = @C.#$
     @C.#_
     @C.#\u{6F}
     @C.#\u2118

test/language/statements/class/decorator/syntax/class-valid/decorator-member-expr-private-identifier.js

@@ -51,6 +51,6 @@ class C {
     @C.#ZW_\u200C_NJ
     @C.#ZW_\u200D_J
     @C.#yield
-    @C.#await class C {}
+    @C.#await class D {}
   }
 }