fix(deps): update node-fetch to 2.6.1

[goatandsheep]

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Fixes #199 🦕

[codecov]

Codecov Report

Merging #200 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #200   +/-   ##
=======================================
  Coverage   81.50%   81.50%           
=======================================
  Files           5        5           
  Lines         676      676           
  Branches       50       50           
=======================================
  Hits          551      551           
  Misses        125      125           

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