LibJS: Add missing CommonPropertyNamess and StringMayBeNumber::Nos

Author: https://github.com/yyny
Commit: 58631e9eef
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2670

Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPropertyID.cpp

@@ -573,6 +573,7 @@ bool is_animatable_property(PropertyID property_id)
 
     properties.for_each_member([&](auto& name, auto& value) {
         VERIFY(value.is_object());
+        VERIFY(!name.is_empty() && !is_ascii_digit(name[0])); // Ensure `PropertyKey`s are not Numbers.
         if (is_legacy_alias(value.as_object()))
             return;