Fix "Lookup Symbol" on global class members

"Lookup Symbol" on global class members now does switch to the relevant script.

modules/gdscript/gdscript_editor.cpp

@@ -2810,6 +2810,7 @@ static Error _lookup_symbol_from_base(const GDScriptParser::DataType &p_base, co
 						r_result.type = ScriptLanguage::LookupResult::RESULT_SCRIPT_LOCATION;
 						r_result.location = base_type.class_type->get_member(p_symbol).get_line();
 						r_result.class_path = base_type.script_path;
+						r_result.script = GDScriptCache::get_shallow_script(r_result.class_path);
 						return OK;
 					}
 					base_type = base_type.class_type->base_type;