ci: Add actions runner env

[peaceiris]

DEBIAN_FRONTEND="noninteractive"
ImageVersion="20200717.1"
GITHUB_SERVER_URL="https://github.com"
GITHUB_GRAPHQL_URL="https://api.github.com/graphql"
GITHUB_ACTOR="peaceiris"
GITHUB_REPOSITORY="actions/pages"
RUNNER_OS="Linux"
RUNNER_USER="runner"
RUNNER_TEMP="/home/runner/work/_temp"
RUNNER_WORKSPACE="/home/runner/work/pages"

[codecov]

Codecov Report

Merging #443 into main will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #443   +/-   ##
=======================================
  Coverage   51.98%   51.98%           
=======================================
  Files           4        4           
  Lines         277      277           
  Branches       49       49           
=======================================
  Hits          144      144           
  Misses        132      132           
  Partials        1        1           

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