Fix up issue with PROGMEM and hand_swap_config (#16027)

quantum/action.h

@@ -19,6 +19,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include <stdint.h>
 #include <stdbool.h>
+#include "progmem.h"
 #include "keyboard.h"
 #include "keycode.h"
 #include "action_code.h"