ip token association is awkward

[zeratax]

Describe the bug
the fix introduced in 4454b3c, is still bad.
the association table currently associates between an ip object and a token object, but since the ip object only has one property it might as well just associate directly between an ip string and the token.

association_table = Table('association', db.Model.metadata,
                          Column('ips', Integer, ForeignKey('ips.id'), primary_key=True),
                          Column('tokens', String(255), ForeignKey('tokens.name'), primary_key=True))

Expected behavior
add alembic version that will recreate the association_table properly. should work very similarly to the last fix:
https://github.com/ZerataX/matrix-registration/blob/4454b3cbf222356e2ef2eda695f5ce9a8431c835/alembic/versions/130b5c2275d8_update_ip_token_association.py#L23-L44

downgrading it will first have to create a new ip table and then recreate an association table with the proper ids to tokens associated