fix(css_parser): accept more valid CSS identifiers (#3771)

CHANGELOG.md

@@ -555,6 +555,19 @@ our [guidelines for writing a good changelog entry](https://github.com/biomejs/b
 
 #### Bug fixes
 
+- The CSS parser now accepts emoji in identifiers ([3627](https://github.com/biomejs/biome/issues/3627)).
+
+  The following code is now corretcly parsed:
+
+  ```css
+  p {
+    --🥔-color: red;
+    color: var(--🥔-color);
+  }
+  ```
+
+  Contributed by @Conaclos
+
 - Fix [#3287](https://github.com/biomejs/biome/issues/3287) nested selectors with pseudo-classes. Contributed by @denbezrukov
 
 - Fix [#3349](https://github.com/biomejs/biome/issues/3349) allow CSS multiple ampersand support. Contributed by @denbezrukov

crates/biome_css_analyze/tests/specs/nursery/noIrregularWhitespace/invalid.css.snap

@@ -139,14 +139,14 @@ invalid.css:4:2 lint/nursery/noIrregularWhitespace ━━━━━━━━━
 ```
 
 ```
-invalid.css:6:12 lint/nursery/noIrregularWhitespace ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+invalid.css:6:2 lint/nursery/noIrregularWhitespace ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
 
   ! Irregular whitespace found.
   
     4 │ @layer↡module, state;
     5 │ /* \u{feff} */
   > 6 │ .firstClass�.secondClass {
-      │            ^
+      │  ^^^^^^^^^^^
     7 │ 	padding: 10px;
     8 │ }
   

crates/biome_css_formatter/tests/specs/prettier/css/atrule/debug.css.snap

@@ -80,6 +80,29 @@ info: css/atrule/debug.css
 @debug $very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-long-var + $very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-long-var;
 ```
 
+# Errors
+```
+debug.css:22:8 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  × unexpected character `$`
+
+    21 │ ;
+  > 22 │ @debug $very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-long-var + $very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-long-var;
+       │        ^
+    23 │ 
+
+debug.css:22:95 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  × unexpected character `$`
+
+    21 │ ;
+  > 22 │ @debug $very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-long-var + $very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-long-var;
+       │                                                                                               ^
+    23 │ 
+
+
+```
+
 # Lines exceeding max width of 80 characters
 ```
    15: @debug $very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-long-var + $very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-long-var;