has_one relationship not working as expected.

[josephmancuso]

Describe the bug
has_one relationship not working as expected.

To Reproduce
Steps to reproduce the behavior:

1. Create a model
2. use the with_ method to get the has one related model.
3. You will hit a None type issue if one of the records are None
4. One of the records should be NULL in order to reproduce the None query bindings

Expected behavior
Should exclude the None types from the query

Screenshots
Screenshots help a lot. If applicable, add screenshots to help explain your problem.
"that is exactly what I do. but because buyer_id might be NULL (no buyer yet) the second query fails:"

query: 'SELECT * FROM "users" WHERE "users"."None" IN (?)'
Binding ('2',)

What database are you using?

• Type: [e.g. Postgres, MySQL, SQLite]
• Version [e.g. 8, 9.1, 10.5]

Additional context