[css-syntax-3] Do not consume ; to consume a declaration

[cdoublev]

; is consumed as part of the declaration value (eg. in @supports (color: green;) {}) whereas it cannot be matched by <declaration> (railroad diagram).

I suggest this change in step 5 of consume a declaration:

- * As long as the next input token is anything other than an <EOF-token>, 
+ * As long as the next input token is anything other than an <EOF-token> or <semicolon-token>, 
    consume a component value and append it to decl’s value.

[cdoublev]

Fixed in 6ab5888.