* Modify the function implementation of ESP32-S2 RTC GPIO
On ESP32 those PADs which have RTC functions must set pullup/down/capability via RTC register.
On ESP32-S2, Digital IOs have their own registers to control pullup/down/capability, independent with RTC registers.
* Add ESP32-S2 support of unit test
* Modify the pull-up test of unit test
* Modify the interrupt test of unit test
* Modify input and output mode test of unit test
