Fix inconsistent MATRIX_COLS: basekeys/slice (#9022)

keyboards/basekeys/slice/rev1/config.h

@@ -28,7 +28,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 /* key matrix size */
 #define MATRIX_ROWS 10
-#define MATRIX_COLS 18
+#define MATRIX_COLS 9
 
 // wiring of each half
 #define MATRIX_ROW_PINS { D4, C6, D7, E6, B4 }

keyboards/basekeys/slice/rev1_rgb/config.h

@@ -28,7 +28,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 /* key matrix size */
 #define MATRIX_ROWS 10
-#define MATRIX_COLS 18
+#define MATRIX_COLS 9
 
 // wiring of each half
 #define MATRIX_ROW_PINS { D4, C6, D7, E6, B4 }