Auto merge of #23117 - asajeffrey:mach-magicleap-package-target, r=jdm

Set the target when packaging for magicleap

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If we don't set the target during packaging, we get errors checking for gstreamer.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because it fixes packaging errors.

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python/servo/package_commands.py

@@ -212,6 +212,11 @@ class PackageCommands(CommandBase):
             android = self.handle_android_target(target)
         else:
             target = self.config["android"]["target"]
+        if target and magicleap:
+            print("Please specify either --target or --magicleap.")
+            sys.exit(1)
+        if magicleap:
+            target = "aarch64-linux-android"
         env = self.build_env(target=target)
         binary_path = self.get_binary_path(release, dev, android=android, magicleap=magicleap)
         dir_to_root = self.get_top_dir()