feat: allow SQLAlchemy 1.4 use - #198

Hi @larkee, I'm adding you as a reviewer, please have a look at if you get some time this week.

Still trying to fix tests here. I've figured out that if I move a test file to the root folder, it's visible for pytest. But in test folder it always gives 0 collected. So, the problem is somehow related to the folder name/location, it's only left to understand what's exactly wrong.

Still trying to fix tests here. I've figured out that if I move a test file to the root folder, it's visible for pytest. But in test folder it always gives 0 collected. So, the problem is somehow related to the folder name/location, it's only left to understand what's exactly wrong.

Thanks Ilya for the update

@asthamohta, only this bizarre error left with SQLAlchemy 1.3.

I'm thinking what if we'll just drop tests for SQLAlchemy 1.3? Right now new changes for SQLAlchemy 1.3 are pretty rare and they are only about fixing bugs, not functionality. I suspect we have problems here just because 1.3 is not very supported already, so the old test suite wasn't properly updated for the new pytest versions, that's why 1.4 tests are working fine, while 1.3 are not collected (seems like it's happening because of __init__ methods of the test cases). Maybe let's simply drop the 1.3 test session and stick to 1.4? Erasing the double of the test suite for 1.3 should make our life easier.