Use the esp32 wifi coprocessor on the PyPortal

[stillinbeta]

Summary

[describe your changes here]

Checklist

• All new or modified code is well documented, especially public items
• No new warnings or clippy suggestions have been introduced - CI will deny clippy warnings by default! You may #[allow] certain lints where reasonable, but ideally justify those with a short comment.

If Adding a new Board

• Board CI added to crates.json
• Board is properly following "Tier 2" conventions, unless otherwise decided to be "Tier 1"

If Adding a new cargo feature to the HAL

• Feature is added to the test matrix for applicable boards / PACs in crates.json

% cargo run --example embassy_wifi --features wifi,embassy-time,defmt --release
   Compiling pyportal v0.11.0 (/home/ellie/Projects/pyportal/atsamd-pyportal/boards/pyportal)
    Finished `release` profile [optimized + debuginfo] target(s) in 1.89s
     Running `probe-rs run --chip ATSAMD51J20A --speed=2000 /home/ellie/Projects/pyportal/atsamd-pyportal/target/thumbv7em-none-eabihf/release/examples/embassy_wifi`
      Erasing ✔ 100% [####################]  48.00 KiB @  65.83 KiB/s (took 1s)                                                                                    Programming ✔ 100% [####################]  46.50 KiB @   6.66 KiB/s (took 7s)                                                                                       Finished in 7.82s
Hello world!
trying to init wifi
wifi awake
Firmware version is 2.0.0-rc.0+adafruit
sending credentials
waiting for connection
connected!
IP: {"ip":"216.232.176.17"}