fix(belongs-to): create now returns target model

[Munter]

Pull Request check-list

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• Does npm run test or npm run test-DIALECT pass with this change (including linting)?
• Does the description below contain a link to an existing issue (Closes #[issue]) or a description of the issue you are solving?
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Description of change

Closes #8716

[codecov]

Codecov Report

Merging #9980 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #9980      +/-   ##
==========================================
+ Coverage   96.38%   96.38%   +<.01%     
==========================================
  Files          63       63              
  Lines        9388     9389       +1     
==========================================
+ Hits         9049     9050       +1     
  Misses        339      339

Impacted Files	Coverage Δ
lib/associations/has-one.js	97.11% <ø> (ø)	⬆️
lib/associations/belongs-to.js	100% <100%> (ø)	⬆️

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[sushantdhiman]

Thanks @Munter