Talk about async executors in the FAQ (or some other section)

[jessebraham]

We have been getting a number of questions in Matrix recently regarding async executors, and which executors are supported by which HALs. We should write some content about this so that we can just link to it instead of having to repeat ourselves so often.

[SergioGasquez]

The following conversation on Matrix has good information that can help when writing this section

[ivmarkov]

The situation has evolved since then in that async-io 2.0 (in smol) has out of the box support for ESP IDF.
Also the changes to tokio are released in the meantime as well, I think.
Last but not least, esp-idf-* do not require anymore a specific executor for the async drivers. Any executor from above would work. Also embassy-executor should work, with the std feature enabled.