chore(deps): update dependency nuxt to v2.15.6

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
nuxt	2.15.5 -> 2.15.6

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Release Notes

nuxt/nuxt.js

v2.15.6

Compare Source

🐛 Bug Fixes

• types
  • #​9270 Pin to @types/webpack-dev-middleware@4.1.2 (resolves #​9268)

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Configuration

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[codecov]

Codecov Report

Merging #197 (3921911) into master (5602f34) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #197   +/-   ##
=======================================
  Coverage   96.07%   96.07%           
=======================================
  Files           2        2           
  Lines          51       51           
  Branches       13       13           
=======================================
  Hits           49       49           
  Misses          2        2