Update .github/workflows/ci-e2e-openshift.yaml

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: clubanderson

.github/workflows/ci-e2e-openshift.yaml

@@ -101,8 +101,8 @@ jobs:
           GIT_REF: ${{ github.event.pull_request.head.sha || github.sha }}
         run: |
           # Build image with git ref tag for this PR
-          # Use first 8 chars of the git ref
-          IMAGE_TAG="ref-${GIT_REF::8}"
+          # Use first 8 chars of the git ref (POSIX-compliant)
+          IMAGE_TAG="ref-$(printf '%s' "$GIT_REF" | cut -c1-8)"
           FULL_IMAGE="${REGISTRY}/${IMAGE_NAME}:${IMAGE_TAG}"
           echo "Building image: $FULL_IMAGE"
           echo "Git ref: $GIT_REF"