Agency property does not account for None values

[rachidatecs]

Current Behavior

If an Agency does not exist, the property converted_federal_agency in the domainInformation model will cause an error that causes admin/domains to return a 500

This issue was already handled for domainRequests.

Expected Behavior

If an agency does not exist, the domains list should still return a 302 and the record for the domain with the missing federal agency should resolve. Federal agency should show as None, or empty.

Steps to Reproduce

1. This is reproducible on the DK sandbox, which contains a large dataset with records that trigger this condition.

Environment

No response

Additional Context

The fix should match the pattern on domainRequests (or the pattern on domainRequests should be revised to match the fix implemented for domainInformation)

Issue Links

Relates to #2852