docs: Change ADC default resolution exception to ESP32-S2

Author: eMUQI

docs/en/api/adc.rst

@@ -52,7 +52,8 @@ This function will return analog value in millivolts (calibrated).
 analogReadResolution
 ^^^^^^^^^^^^^^^^^^^^
 
-This function is used to set the resolution of ``analogRead`` return value. Default is 12 bits (range from 0 to 4095).
+This function is used to set the resolution of ``analogRead`` return value. Default is 12 bits (range from 0 to 4095)
+for all chips except ESP32-S2 where default is 13 bits (range from 0 to 8191).
 When different resolution is set, the values read will be shifted to match the given resolution.
 
 Range is 1 - 16 .The default value will be used, if this function is not used.