ci: build on the correct github runners (#107)

Author: raymondk

dist-workspace.toml

@@ -20,3 +20,6 @@ dist = true
 
 [dist.github-custom-runners]
 global = "ubuntu-latest"
+x86_64-unknown-linux-gnu = "ubuntu-latest"
+x86_64-apple-darwin = "macos-13"
+aarch64-apple-darwin = "macos-latest"