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Automatically verify that derive() lists are alphabetically ordered #18172
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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 fix#18172 (github issue number if applicable).
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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because _____
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Source-Repo: https://github.com/servo/servo
Source-Revision: 474369618965569407d127b1e8c481e757cc59d3
