windows: add a way to install rustfmt alongside MSI-based rust installation

[ikostia]

For various reasons, I use MSI-based stable rust installer on Windows. For such an installation flavor, there seems to be no way to install rustfmt:

• I can't use rustup, because it's MSI installation
• I can't build it from source, because I use stable compiler

Can this be fixed or are there any workarounds?

[topecongiro]

To fix this we could put pre-built binaries on the release page, but even then I am not sure if you could run those binaries without installing the nightly.

[topecongiro]

Starting from the 2.0 release, we will provide pre-built binaries for Windows/macOS/Linux.

[calebcartwright]

@topecongiro - what are your thoughts on doing something like a tag-push based trigger in a GHA workflow that will create the pre-built binaries (presumably for all Tier 1 platforms) and create the GitHub Release with that tag and binaries as artifacts?

[topecongiro]

@calebcartwright Yeah, adding some kind of automation as you described is what I have in mind.

[SpecterShell]

@topecongiro The pre-built binary was not statically built and requires a library file that does not match the one in the latest stable Rust MSI installer.