Update dependency @types/jest to v26.0.15

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
@types/jest	devDependencies	patch	26.0.14 -> 26.0.15

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[coveralls]

Pull Request Test Coverage Report for Build 317156795

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 100.0%

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Totals
Change from base Build 314380829:	0.0%
Covered Lines:	197
Relevant Lines:	197

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💛 - Coveralls

[codecov]

Codecov Report

Merging #96 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master       #96   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           10        10           
  Lines          202       202           
  Branches        24        24           
=========================================
  Hits           202       202           

Flag	Coverage Δ
#unittests	100.00% <ø> (ø)

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