Fix bulk_update when using a pk other than id

[abvf]

In method bulk_update, the primary key name is hard-coded as "id"; therefore, it throws an error when using a primary key with a name other than id.

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added the changelog accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[coveralls]

Pull Request Test Coverage Report for Build 10239333398

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Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 89.09%

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Totals
Change from base Build 10196201661:	0.0%
Covered Lines:	5960
Relevant Lines:	6575

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💛 - Coveralls

[abondar]

Hi!

Thanks for your submission
Could you please add some kind of test that reproduces issue?
You can write it somewhere here https://github.com/tortoise/tortoise-orm/blob/develop/tests/test_update.py#L37

[abvf]

Hi @abondar,

I have added a test with the Event model, as its primary key is not id. The test will fail without the fix committed in this pull request.