fix(dialog): Pin rfd to 0.12 to prevent freeze on Linux (#796)

* Do not use rfd 0.12.1

https://github.com/PolyMeilex/rfd/pull/152
conflicts with the way tauri uses it.

> Yeah, this is a decent solution, not much else we can do about this global state bs on C side.
>
> This will obviously blow up as soon as someone has other code that also uses GTK, but let's ignore that for now, as I want to get rid of GTK backend one day anyway (#66).

Yes, Tauri is other code that also uses GTK, and it does, indeed, blow up. The best way around this is to stop using rfd entirely (they're planning to drop the GTK backend, which will probably break since the XDG Portal API doesn't cover message dialogs).

* Update dialog-pin-rfd.md

---------

Co-authored-by: Fabian-Lars <fabianlars@fabianlars.de>

Cargo.lock

@@ -4622,9 +4622,9 @@ dependencies = [
 
 [[package]]
 name = "rfd"
-version = "0.12.1"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c9e7b57df6e8472152674607f6cc68aa14a748a3157a857a94f516e11aeacc2"
+checksum = "241a0deb168c88050d872294f7b3106c1dfa8740942bcc97bc91b98e97b5c501"
 dependencies = [
  "block",
  "dispatch",