WiFiS3 At improvements

[andreagilardoni]

Improving the AT parsing function

[pennam]

Testing core sketches using AT commands: OTA :+1: StartCounter :+1: Prefs2Struct :+1: SATSECertificate :-1: Timeout error SATSEPrivateKey :+1: SATSERandomNumber :+1: SATSESerialNumber :+1: SATSESignAndVerify :-1: WiFiWebServer :+1: WiFiWebClientSSL :+1: WiFiWebClientRepeating :+1:

[andreagilardoni]

Fixed the issue that was making the tests @pennam mentioned in the previous comment: https://github.com/andreagilardoni/ArduinoCore-renesas/blob/649ecb8b5fa2665fc555a1cd29440b85b6614cac/libraries/WiFiS3/src/Modem.cpp#L229 The issue is that we cannot check the response prompt in passthrough mode since we lack the knowledge of the previously sent command. The line will be preserved with a comment indicating that when solved this could help improving the reliability of the protocol, since it enforces a command to have a response with a matching prompt.

[pennam]

Testing core sketches using AT commands:

Sketch	0.5.0	0.4.1
OTA	:+1:	:+1:
StartCounter	:+1:	:+1:
Prefs2Struct	:+1:	:+1:
SATSECertificate	:+1:	:+1:
SATSEPrivateKey	:+1:	:+1:
SATSERandomNumber	:+1:	:+1:
SATSESerialNumber	:+1:	:+1:
SATSESignAndVerify	:+1:	:+1:
WiFiWebServer	:+1:	:+1:
WiFiWebClientSSL	:+1:	:+1:
WiFiWebClientRepeating	:+1:	:+1: