fix(api): change the inserted_at.lte unittest

[AdriiiPRodri]

Context

In this PR we are going to fix an error detected in the unit tests of the API, specifically this error is related to the insertion date of a finding.

Checklist

• Are there new checks included in this PR? No
  • If so, do we need to update permissions for the provider? Please review this carefully.
• Review if the code is being covered by tests.
• Review if code is being documented following this specification https://github.com/google/styleguide/blob/gh-pages/pyguide.md#38-comments-and-docstrings
• Review if backport is needed.

License

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.78%. Comparing base (80311d3) to head (35be4ce).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6403      +/-   ##
==========================================
+ Coverage   90.10%   93.78%   +3.67%     
==========================================
  Files        1183       65    -1118     
  Lines       36333     6211   -30122     
==========================================
- Hits        32738     5825   -26913     
+ Misses       3595      386    -3209     

Flag	Coverage Δ
api	93.78% <ø> (?)
prowler	?

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Components	Coverage Δ
prowler	∅ <ø> (∅)
api	93.78% <ø> (∅)