[CI] run PKGBUIlD's function CHECK if env var CI_MAKEPKG_RUN_CHECK is…

… set

This allows developpers to run the check function by simply defining the
fork's env variable CI_MAKEPKG_RUN_CHECK.

Rf.: How to set an environment variable for a repository:
https://docs.github.com/en/actions/learn-github-actions/variables#creating-configuration-variables-for-a-repository

.ci/ci-build.sh

@@ -126,14 +126,21 @@ pacman -R --recursive --unneeded --noconfirm --noprogressbar git python
 # Enable linting
 export MAKEPKG_LINT_PKGBUILD=1
 
+# Run function CHECK if env var CI_MAKEPKG_RUN_CHECK is set (to any value)
+if test "${CI_MAKEPKG_RUN_CHECK+set}" = set; then
+    MAKEPKG_RUN_CHECK_FLAG=''
+else
+    MAKEPKG_RUN_CHECK_FLAG='--nocheck'
+fi
+
 message 'Building packages'
 for package in "${packages[@]}"; do
     echo "::group::[build] ${package}"
     execute 'Clear cache' pacman -Scc --noconfirm
     execute 'Fetch keys' "$DIR/fetch-validpgpkeys.sh"
     cp -r ${package} B && cd B
     message 'Building binary'
-    makepkg-mingw --noconfirm --noprogressbar --nocheck --syncdeps --rmdeps --cleanbuild || failure "${status} failed"
+    makepkg-mingw --noconfirm --noprogressbar --syncdeps --rmdeps --cleanbuild "${MAKEPKG_RUN_CHECK_FLAG}" || failure "${status} failed"
     cd - > /dev/null
     repo-add $PWD/artifacts/ci.db.tar.gz $PWD/B/*.pkg.tar.*
     pacman -Sy