A way to "merge" sponsor objects in python.org/admin

[loren-c]

Is your feature request related to a problem? Please describe.
Sometimes when submitting an application on our sponsor application page , sponsors will unintentionally create a second sponsor object for the same company.

This creates problems with populating renewal dates among other things--If the contract is a renewal, but it is not connected to the sponsor object associated with the last contract, the date of last contract is "UNKNOWN" and when I try to download the renewal contract I get a 500 error.

Describe the solution you'd like
It would be nice to have a way in https://www.python.org/admin/sponsors/sponsor/ to merge duplicate sponsor objects. Ideally they would retain the information/files from the most recently created sponsor object and/or ask which to retain.

Describe alternatives you've considered
Currently I haven't been able to find a way to generate a renewal contract in the case of duplicate sponsor objects, so I've just been manually creating the contract from the template in those cases. (E.g. frequently the sponsor contacts change from year to year, and sometimes the logo gets updated or other details change.)

Additional context

@ewdurbin

[JacobCoffee]

As a side note, maybe we should restrict the sponsor field name to be unique to prevent the users from doing this