🔨 Firmware rename followup (#25966)

Followup to #25957

ini/stm32f4.ini

@@ -684,7 +684,7 @@ board                       = genericSTM32F401RC
 board_build.variant         = MARLIN_CREALITY_STM32F401RC
 board_build.offset          = 0x10000
 board_upload.offset_address = 0x08010000
-board_build.rename          = firmware-{date}-{time}
+board_build.rename          = firmware-{date}-{time}.bin
 build_flags                 = ${stm32_variant.build_flags} -DMCU_STM32F401RC -DSTM32F4
                               -DSS_TIMER=4 -DTIMER_SERVO=TIM5
                               -DENABLE_HWSERIAL3 -DTRANSFER_CLOCK_DIV=8
@@ -709,7 +709,7 @@ extends                     = stm32_variant
 board                       = marlin_CREALITY_STM32F401RE
 board_build.offset          = 0x10000
 board_upload.offset_address = 0x08010000
-board_build.rename          = firmware-{date}-{time}
+board_build.rename          = firmware-{date}-{time}.bin
 build_flags                 = ${stm32_variant.build_flags} -DSTM32F401xE -DSTM32F4 -DSTM32F4_UPDATE_FOLDER
 build_unflags               = ${stm32_variant.build_unflags} -DUSBCON -DUSBD_USE_CDC
 monitor_speed               = 115200