Set DOCKER_CONFIG environment variable in CI and coverage workflows (#8128)

Author: glen-84

.github/workflows/ci.yml

@@ -162,6 +162,8 @@ jobs:
     runs-on: ubuntu-latest
     needs: [configure, check-changes]
     if: needs.check-changes.outputs.library_changes == 'true'
+    env:
+      DOCKER_CONFIG: $HOME/.docker
 
     strategy:
       fail-fast: false

.github/workflows/coverage.yml

@@ -44,6 +44,8 @@ jobs:
     name: Run ${{ matrix.name }}
     runs-on: ubuntu-latest
     needs: configure
+    env:
+      DOCKER_CONFIG: $HOME/.docker
 
     strategy:
       fail-fast: false