Add automated build workflow for Android

[hjiangsu]

Pull Request Description

This PR adds a new GitHub workflow that automatically builds nightly/general release builds for Android. I've opted to only work on the automated Android build for now as iOS requires a bit more effort to get set up (in particular, I would need to generate new provisioning profiles and certificates to perform automatic builds)

With the Android automated builds, I'll also be able to (hopefully) finalize the requirements needed for F-Droid reproducible builds. Once this PR is merged and a new nightly is built, I'll be able to verify that the F-Droid build process works as intended.

The next step after automating Android builds is to generate a template release markdown file to automatically populate the release notes!

Issue Being Fixed

Issue Number: N/A

Screenshots / Recordings

Checklist

• If a new package was added, did you ensure it uses an appropriate license and is actively maintained?
• Did you use localized strings (and added appropriate descriptions) where applicable?
• Did you add semanticLabels where applicable for accessibility?

[micahmo]

This is awesome!

[hjiangsu]

@micahmo This is ready to be reviewed - if you could, please look over the workflow and let me know if there's something that I might be missing here as I'm not too familiar with GitHub actions/workflows!

I've also updated the PR description to provide a bit more details.

[micahmo]

I would need to generate new provisioning profiles and certificates to perform automatic builds

I'm not sure if it helps at all, but remember that you can upload secrets to the repository (Settings > Secrets and variables > Actions) which can be consumed in the actions. Maybe that will help to reuse existing certificates and such?

[micahmo]

This looks great! I'm sure it will really help to simplify your process!

[hjiangsu]

I'm not sure if it helps at all, but remember that you can upload secrets to the repository (Settings > Secrets and variables > Actions) which can be consumed in the actions. Maybe that will help to reuse existing certificates and such?

I'm doing this for the Android secrets! However, for iOS, there are a few certificates that are automatically managed by Xcode. This means that I would have to re-create those certificates and replace them first before I can add them into GitHub

[micahmo]

Gotcha!