CI: fix cargo-binstall and pixi warning (#3891)

Nightly CI runs broke because of a install error with `cargo-binstall`,
fixed it by bumping version in pixi config.

Also fix a warning in pixi (`project` -> `workspace`), and bump the pixi
version in CI to latest.

Author: luizirber

.github/workflows/dev_envs.yml

@@ -37,7 +37,7 @@ jobs:
     - name: set up pixi
       uses: prefix-dev/setup-pixi@v0.9.3
       with:
-        pixi-version: v0.53.0
+        pixi-version: v0.63.2
         cache: true
         frozen: true
 

.github/workflows/rust.yml

@@ -10,7 +10,7 @@ on:
     - cron: "0 0 * * *" # daily
 
 env:
-  PIXI_VERSION: "v0.53.0"
+  PIXI_VERSION: "v0.63.2"
 
 jobs:
   check: