Add functionality to apply tokens to xml catalog directly
Following from lhcb/Stripping!1722 (merged), it was seen that there is a use case for having a function to directly apply token to xml file catalogs.
A function was adding to the stripping project here: https://gitlab.cern.ch/lhcb/Stripping/-/blob/857e18f123f3f55e9c123490d5e88230b8276773/Phys/StrippingSelections/tests/CI/DataAuthentication.py
Adding the same functionality directly to the apd package would be great.