Auto merge of #16466 - pyfisch:text-combine-upright-no-number, r=emilio

Remove comment about text-combine-upright digits.

The digits value was never implemented and was dropped from the spec. Old issues like #13769 still discussed if this value should be implemented.

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components/style/properties/longhand/inherited_text.mako.rs

@@ -1274,9 +1274,6 @@ ${helpers.single_keyword("ruby-position", "over under",
 // CSS Writing Modes Module Level 3
 // https://drafts.csswg.org/css-writing-modes-3/
 
-// The spec has "digits <integer>?" value in addition. But that value is
-// at-risk, and Gecko's layout code doesn't support that either. So we
-// can just take the easy way for now.
 ${helpers.single_keyword("text-combine-upright", "none all",
                          products="gecko", animation_type="none",
                          spec="https://drafts.csswg.org/css-writing-modes-3/#text-combine-upright")}