chore(deps): update dependency @types/koa to v3

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
@types/koa (source)	2.15.0 -> 3.0.0

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.84%. Comparing base (c0593e6) to head (2348220).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2963   +/-   ##
=======================================
  Coverage   89.84%   89.84%           
=======================================
  Files         188      188           
  Lines        9272     9272           
  Branches     1901     1901           
=======================================
  Hits         8330     8330           
  Misses        942      942           

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