Updating ESP8266 Espressif framework

Author: thorrak

platformio.ini

@@ -113,8 +113,8 @@ monitor_filters =
     esp32_exception_decoder
 
 [env:esp8266_wifi]
-; The latest platform has a bug that causes SIGNIFICANT inconsistency in connecting to WiFi. Rolling back for now.
-platform = espressif8266@4.1.0
+; v4.1.0 was known to be more stable with WiFi - but trying 4.2.1 to see if the issues have been fixed
+platform = espressif8266@4.2.1
 board = d1_mini
 framework = ${common.framework}
 board_build.filesystem = littlefs