Fixes #33419 - Introduce Fact Parser Registry

FactParser class has two purposes in current codebase. It acts as parent
for other fact parses (PuppetFactParser, AnsibleFactParser,
RhsmFactParser...) and also as a registry for registering parsers for
given type/key. This PR introduces FactParserRegistry under
Foreman::Plugin namespace. Thanks to that, the FactParser
can takes care only for facts!