Fix OS_UWP::execute's signature after cd4449e

Same as #28919.

platform/uwp/os_uwp.cpp

@@ -713,7 +713,7 @@ void OS_UWP::set_custom_mouse_cursor(const RES &p_cursor, CursorShape p_shape, c
 	// TODO
 }
 
-Error OS_UWP::execute(const String &p_path, const List<String> &p_arguments, bool p_blocking, ProcessID *r_child_id, String *r_pipe, int *r_exitcode, bool read_stderr) {
+Error OS_UWP::execute(const String &p_path, const List<String> &p_arguments, bool p_blocking, ProcessID *r_child_id, String *r_pipe, int *r_exitcode, bool read_stderr, Mutex *p_pipe_mutex) {
 
 	return FAILED;
 };

platform/uwp/os_uwp.h

@@ -208,7 +208,7 @@ public:
 	virtual void delay_usec(uint32_t p_usec) const;
 	virtual uint64_t get_ticks_usec() const;
 
-	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false);
+	virtual Error execute(const String &p_path, const List<String> &p_arguments, bool p_blocking, ProcessID *r_child_id = NULL, String *r_pipe = NULL, int *r_exitcode = NULL, bool read_stderr = false, Mutex *p_pipe_mutex = NULL);
 	virtual Error kill(const ProcessID &p_pid);
 
 	virtual bool has_environment(const String &p_var) const;