servo: Merge #18179 - Automatically verify that derive() lists are alphabetically ordered #… (from davidcl:master); r=jdm

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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

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 421aa68def8e17f70580477a4203494db3b69382