fix(scope): don't modify original scope definition

[sushantdhiman]

Pull Request check-list

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• 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 #12172

[codecov]

Codecov Report

Merging #12207 into master will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master   #12207   +/-   ##
=======================================
  Coverage   96.34%   96.34%           
=======================================
  Files          95       95           
  Lines        9181     9181           
=======================================
  Hits         8845     8845           
  Misses        336      336           

Impacted Files	Coverage Δ
lib/model.js	96.60% <100.00%> (ø)

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