MYFACES-4442: Fix UnsupportedOperationException during Faces init

[pnicolucci]

This fixes MYFACES-4442: https://issues.apache.org/jira/browse/MYFACES-4442

I had to rummage around in the commit history of the current branches and find where these classes used to reside:

1. ServletMapping
2. WebXml I updated this class to correct javax->jakarta, ClassUtils current package, updated import for DelegatedFacesServlet, and updated package for WebXmlParser.
3. WebXmlParser Already existed. History of WebXmlParser I added the following back to it and modified it as necessary to fit into the latest code base: This is what it looked like before it was moved in the same commit. The readWebApp method was updated to read the different mappings , which was removed here.
4. WebXmlParserErrorHandler
5. WebXmlParserUtils

[tandraschko]

I think the fallback should be directly in FacesServletMappingUtils.getFacesServletRegistration

AFAICS we dont scan web-fragments? Thats a must have

[pnicolucci]

@tandraschko I have another idea and I think we can avoid this web.xml parsing altogether. I'll work to get a new PR to share my findings and we can discuss.