feat(css/parser): normalize and improve function name

[alexander-akait]

Description:

Improve function name:

1. Normalize name (lowercase)
2. Use dashed ident (we use the same for at-rules/declarations)

From spec (https://www.w3.org/TR/css-values-4/#dashed-idents):

CSS will use more in the future, as more author-controlled syntax is added. CSS authoring tools, such as preprocessors that turn custom syntax into standard CSS, should use as well, to avoid clashing with future CSS design.
For example, if a CSS preprocessor added a new "custom" at-rule, it shouldn’t spell it @Custom, as this would clash with a future official @Custom rule added by CSS. Instead, it should use @--custom, which is guaranteed to never clash with anything defined by CSS.

3. use js_word!()

BREAKING CHANGE:

Yes

Related issue (if exists):

No

[alexander-akait]

Rebased

[kdy1]

Why is this required?

[alexander-akait]

@kdy1 Yeah, it reduce code, we have the same for AtRule and Declaration, so we will have less code

[alexander-akait]

@kdy1 Rebased 👍

[kdy1]

swc-bump:

• swc_css_ast --breaking

[swc-bot]

Automated review comment generated by auto-rebase script