Fix Leafony AP03 PB5 pin mapping

Map PB5 to D4, matching digitalPin[4] = PB_5.
The previous value 1 aliases PA2 and targets the wrong GPIO.

Signed-off-by: Shuya Nakagawa <taltalpmh@gmail.com>

Author: taltalp

variants/STM32L4xx/L452RC(I-T-Y)_L452RE(I-T-Y)x(P)_L462RE(I-T-Y)/variant_LEAFONY_AP03.h

@@ -19,7 +19,7 @@
 #define PA2                     1
 #define PC7                     2
 #define PB3                     3
-#define PB5                     1
+#define PB5                     4
 #define PB4                     5
 #define PA8                     6
 #define PB12                    7