Safe wrappers for wifi promiscuous

[indexds]

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Submission Checklist 📝

• I have updated existing examples or added new ones (if applicable).
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Pull Request Details 📖

Description

Second part of #246, adds wrappers for esp_wifi_get_promiscuous and esp_wifi_set_promiscuous.

If I find the time I'll make wrappers for those three functions in the todo, though for now this fixes #246.

Testing

Minimal repo, it works.

[ivmarkov]

Just one nit.

[indexds]

ps: you might want to add something like this to your workflows:

on:
push:
paths-ignore:
- README.md
- ...

[ivmarkov]

Thanks!