feat: Support hard_reset without stub (RDT-542)

[Harshal5]

The method hard_reset() of the class EspSerial used the default arguments of the decorator use_esptool(), due to which stub is required for performing a hard_reset().

This support for no_stub allows usage of the package with the newer chips for whom flasher_stub support has not been added yet.

[hfudev]

@dobairoland PTAL! I'm unaware of the side effects if we use no-stub mode for hard reset.

[dobairoland]

In esptool, the stub/no-stub option is linked to the given flashing instruction and not to the reset sequence. So I don't think uploading the stub would be necessary in any scenario for the reset.

@radimkarnis Please correct me if I've missed something.

[radimkarnis]

@dobairoland exactly. It is completely irrelevant for the hard reset if the stub is used or not.

hard_reset should just assert the DTR and RTS lines of the serial port, it doesn't communicate with the ESP in any way.

So essentially this just makes sure that the stub flasher doesn't get uploaded - which is not needed before invoking a hard reset. LGTM

[hfudev]

@dobairoland @radimkarnis Thank you for your explanation!

@Harshal5 Thank you for the PR! I'm merging it.