chore: use ubuntu-*-arm runners instead of custom ones

This allows contributors to test on GitHub hosted Linux ARM64 runners easily now that those runners are available for free for public repositories: https://github.blog/changelog/2025-01-16-linux-arm64-hosted-runners-now-available-for-free-in-public-repositories-public-preview/

.github/workflows/build-python-packages.yml

@@ -47,18 +47,12 @@ jobs:
             $os = $parts[0]
             $arch = if ($parts[1]) {$parts[1]} else {"x64"}
             switch -wildcard ($os) {
-              "*ubuntu*" { $platform = $os.Replace("ubuntu","linux")}
+              "*ubuntu*" { $platform = $os.Replace("ubuntu","linux"); if ($arch -eq "arm64" ) { $os = "${os}-arm" } }
               "*macos*" { $platform = 'darwin' }
               "*windows*" { $platform = 'win32' }
             }
-            
-            if ($configuration -eq "ubuntu-22.04_arm64") {
-              $os = "setup-actions-ubuntu-arm64-2-core"
-            }
-            elseif ($configuration -eq "ubuntu-24.04_arm64") {
-              $os = "setup-actions-ubuntu24-arm64-2-core"
-            }
-            elseif ($configuration -eq "windows-2019_arm64") {
+
+            if ($configuration -eq "windows-2019_arm64") {
               $os = "setup-actions-windows-arm64-4-core"
             }