LibWeb: Disallow non-whitespace tokens after "none" in `transform`

Before this, a declaration like `transform: none yellow 20;` would be
parsed as `transform: none;`. Now it's correctly rejected as invalid.

Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp

@@ -4772,13 +4772,19 @@ RefPtr<StyleValue> Parser::parse_text_decoration_line_value(TokenStream<Componen
 RefPtr<StyleValue> Parser::parse_transform_value(Vector<ComponentValue> const& component_values)
 {
     NonnullRefPtrVector<StyleValue> transformations;
+    auto tokens = TokenStream { component_values };
+    tokens.skip_whitespace();
+
+    while (tokens.has_next_token()) {
+        tokens.skip_whitespace();
+        auto& part = tokens.next_token();
 
-    for (auto& part : component_values) {
-        if (part.is(Token::Type::Whitespace))
-            continue;
         if (part.is(Token::Type::Ident) && part.token().ident().equals_ignoring_case("none")) {
             if (!transformations.is_empty())
                 return nullptr;
+            tokens.skip_whitespace();
+            if (tokens.has_next_token())
+                return nullptr;
             return IdentifierStyleValue::create(ValueID::None);
         }