fix(devcontainer): Add packages required by grpcio

[c10l]

When running pip3 install --user -r zephyr/scripts/requirements.txt (last step on https://zmk.dev/docs/development/setup), grpcio install fails with the following error:

FileNotFoundError: [Errno 2] No such file or directory: c++: c++

This happens due to missing dev tooling in the container.

[huber-th]

Should this rather go into the dev-generic part of https://github.com/zmkfirmware/zmk-docker to include the dev tooling into the dev base image directly rather than just adding it to the devcontainer here?

[c10l]

I'm not sure but I opened one there and referenced this one.

[petejohanson]

I'm... a little hesitant to do this; the reality is, this is coming in from requirements-extras.txt in Zephyr, which has a lot of stuff that is not required for normal users to just build for their keyboards.

We used to only document installing the requirements-base.txt deps from Zephyr, but it looks like that got changed in 82ff6d8 by Joel. @joelspadin is there a specific reason we changed that I don't recall, or could we go back to just recommending the base deps?

[joelspadin]

I don't remember. I probably just copied it from the Zephyr docs somewhere?