Fix tmpDir and defaultContext func

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

.github/workflows/ci.yml

@@ -178,6 +178,13 @@ jobs:
       -
         name: Image digest
         run: echo ${{ steps.docker_build.outputs.digest }}
+      -
+        name: Check digest
+        run: |
+          if [ -z "${{ steps.docker_build.outputs.digest }}" ]; then
+            echo "::error::Digest should not be empty"
+            exit 1
+          fi
       -
         name: Dump context
         if: always()