Avoid awk on macOS

I was hoping they'd have gawk installed, but I guess not.

xtask/src/main.rs

@@ -37,6 +37,9 @@ fn main() -> Result<()> {
 
             bundle(&package, other_args)
         }
+        // This is only meant to be used by the CI, since using awk for this can be a bit spotty on
+        // macOS
+        "known-packages" => list_known_packages(),
         _ => bail!("Unknown command '{command}'\n\n{USAGE_STRING}"),
     }
 }
@@ -124,6 +127,18 @@ fn bundle(package: &str, mut args: Vec<String>) -> Result<()> {
     Ok(())
 }
 
+/// This lists the packages configured in `bundler.toml`. This is only used as part of the CI when
+/// bundling plugins.
+fn list_known_packages() -> Result<()> {
+    if let Some(config) = load_bundler_config()? {
+        for package in config.keys() {
+            println!("{package}");
+        }
+    }
+
+    Ok(())
+}
+
 /// Load the `bundler.toml` file, if it exists. If it does exist but it cannot be parsed, then this
 /// will return an error.
 fn load_bundler_config() -> Result<Option<BundlerConfig>> {