Auto merge of #15174 - DexterHaslem:15165-webkit-text-stroke-sh-ord, r=SimonSapin

make -webkit-text-stroke color and width shorthand no longer sensitive to ordering

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this makes `-webkit-text-stroke` shorthand work with line-width and color in either order.

I added a shorthand parser test to the existing inherited_text test, which wasn't very similar to any of the other tests in there, hope sticking shorthand below the longhand stuff is ok.

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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 #15165 (github issue number if applicable).

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