Removed unicode character classes from 'features not supported' list

regex/doc.go

@@ -153,9 +153,8 @@ returns the 0-group.
 The following features from [regexp] are (currently) NOT supported:
  1. Named capturing groups
  2. Non-greedy operators
- 3. Unicode character classes
+ 3. Embedded flags (flags are instead passed as arguments to [Compile])
- 4. Embedded flags (flags are instead passed as arguments to [Compile])
+ 4. Literal text with \Q ... \E
- 5. Literal text with \Q ... \E
 
 The following features are not available in [regexp], but are supported in my engine:
  1. Lookarounds