Documentation: Database.query methods share docstrings (#13515)

Currently, query arguments in the Spack core are documented on the
Database._query method, where the functionality is defined.

For users of the spack python command, this makes the python builtin
method help less than ideally useful, as help(spack.store.db.query)
and help(spack.store.db.query_local) do not show relevant information.

This PR updates the doc attributes for the Database.query and
Database.query_local arguments to mirror everything after the first
line of the Database._query docstring.