[css-navigation-1] Rename `urlpattern()` to `url-pattern()`

[valtlai]

Spec: https://drafts.csswg.org/css-navigation-1/#urlpattern-function

CSS usually separates multiple words in idents with a hyphen. The name of the URLPattern() constructor consists of two words, so the corresponding CSS function should too. Therefore, I propose renaming urlpattern() to url-pattern().

(This is similar to #12483.)

[SebastianZ]

@dbaron @noamr I think that's something that can be decided on your distretion. Given the resolution in #12483, it should definitely be hyphenated.

Sebastian

[noamr]

SGTM