chore: use nushell in ci

.github/workflows/rust.yml

@@ -99,7 +99,7 @@ jobs:
         )
 
         $exports | ForEach-Object  {
-          $_ | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
+          Add-Content -Path $env:GITHUB_PATH -Value $_
           Log "Added $_ to $env:GITHUB_PATH"
         }