Fixup axon40 lint. (#18409)

Co-authored-by: Ryan <fauxpark@gmail.com>

keyboards/checkerboards/axon40/config.h

@@ -45,4 +45,3 @@
 #define RGBLIGHT_HUE_STEP 8
 #define RGBLIGHT_SAT_STEP 8
 #define RGBLIGHT_VAL_STEP 8
-#define RGB_MATRIX_MAXIMUM_BRIGHTNESS 290