Config.load_file() removes encodings from pyxpdf_data

[ashutoshvarma]

Config.load_file() removes the xpdfrc settings from pyxpdf_data. As pyxpdf_data introduce new encodings with the help of automatic generated xpdfrc and loading another xpdfrc will discard them.

It can be solved by appending the user provided xpdfrc to the pyxpdf_data's xpdfrc.

Config file loading function can be found here:- https://github.com/ashutoshvarma/pyxpdf/blob/40e296979111378fed464e70c10f0d98336fec69/src/pyxpdf/globalconfig.pxi#L35