Rollup merge of #11975 - ConnorGBrewster:package_run_script, r=asajeffrey

put run script in the right folder for packaging

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Puts run servo script in the proper folder for packaging

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #11944 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because fixing packaging script

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python/servo/package_commands.py

@@ -174,7 +174,7 @@ class PackageCommands(CommandBase):
                           '--pref', 'shell.builtin-key-shortcuts.enabled=false',
                           path.join(browserhtml_path, 'out', 'index.html')]
 
-            runservo = os.open(dir_to_package + 'runservo.sh', os.O_WRONLY | os.O_CREAT, int("0755", 8))
+            runservo = os.open(dir_to_package + '/runservo.sh', os.O_WRONLY | os.O_CREAT, int("0755", 8))
             os.write(runservo, "./servo " + ' '.join(servo_args))
             os.close(runservo)
             print("Creating tarball")