* add base spec model
* fix usage of state_checkpoint_interval in case it is dynamic
* add schema base models, fix spelling, signatures and polishing
Co-authored-by: Eugene Kulak <kulak.eugene@gmail.com>
* Add support for headers to OAuth2Authenticator
Send custom headers in `refresh_access_token()`.
* Bump version + update CHANGELOG.md
* Add tests
* Update tests for refresh_access_token()
* Assert that mock_refresh_token_call was called
* Remove init file