Improve android build script for F-Droid

[maelchiotti]

Fixes #375

[maelchiotti]

@GregoryConrad Here is my PR to improve the android build script for F-Droid. I have successfully tried it with my app in my CI.

• I added the --locked
• An architecture to build can be passed to the script as an argument. If none is passed then the tar.gz archive is built as before. But if an architecture is passed then only this one is built.

[GregoryConrad]

You don’t need a new release for this right? Just need the commit on main for your git submodule? (Making a new release of mimir is a bit of a chore, despite all the automation I’ve built up)

[maelchiotti]

Yeah a new release shouldn't be necessary!