Include the old convension to call nexsu_parser in the aliases list.

[RubelMozumder]

closes #773

In some previous version of pynxtools, we registered the nexus parser in a different way, pynxtools.nomad.entrypoints:nexus_parser. But later changing the entry point name to pynxtools.nomad.parsers:nexus_parser causes an error in nomad. This is fixed by adding the old convention in aliases in NexusParserEntryPoint.

I tested if the aliases are registered properly.

In [1]: from nomad.parsing.parsers import match_parser, parser_dict, parsers

In [2]: for k, v in parser_dict.items():
   ...: 
   ...:     if 'pynxtools' in k:
   ...:         print(f"EntryPoint: {k}")
   ...:
EntryPoint: pynxtools.nomad.parsers:nexus_parser
EntryPoint: pynxtools.nomad.entrypoints:nexus_parser

[lukaspie]

It looks good, but we need to check it works. I guess we can only find out if we reprocess older data in production (like what was reported in the issue). @lauri-codes that probably solves the issue, right?

[RubelMozumder]

It looks good, but we need to check it works. I guess we can only find out if we reprocess older data in production (like what was reported in the issue). @lauri-codes that probably solves the issue, right?

Yeah, I logically checked if aliases refer to the correct entry point.

In [4]: for k, v in parser_dict.items():
   ...: 
   ...:     if 'pynxtools' in k:
   ...:         print(f"Entry point :\n {k}: {v}")
   ...: 
Entry point :
 pynxtools.nomad.parsers:nexus_parser: pynxtools.nomad.parsers:nexus_parser
Entry point :
 pynxtools.nomad.entrypoints:nexus_parser: pynxtools.nomad.parsers:nexus_parser