Implement ESP32-S2 opcodes

In summary, these are the most important changes:
* the `sub_opcode` field on all opcodes except ST have been shrunk
  from 3 bits down to 2 bits
* the LD and ST opcodes support more variations (new instructions)
* branching instructions have changed. The JUMPR instruction uses
  different comparisons and the JUMPS instruction now implements all
  comparisons in hardware, without requiring multiple instructions
  to emulate any comparison.
* There is no more SLEEP instruction to select a sleep timer. Since
  Espressif chose to simply convert SLEEP instructions into WAIT
  instructions we're doing the same.

Update integration tests to run for both the ESP32 and ESP32-S2.

Author: wnienhaus