Add common label to Dockerfiles (#10803)

images/kube-webhook-certgen/rootfs/Dockerfile

@@ -23,6 +23,9 @@ RUN CGO_ENABLED=0 GOOS=linux GOARCH=${TARGETARCH} go build -a -o kube-webhook-ce
 FROM --platform=$BUILDPLATFORM gcr.io/distroless/static:nonroot
 ARG BUILDPLATFORM
 ARG TARGETARCH
+
+LABEL org.opencontainers.image.source=https://github.com/kubernetes/ingress-nginx
+
 WORKDIR /
 COPY --from=builder /workspace/kube-webhook-certgen /kube-webhook-certgen
 USER 65532:65532

images/nginx/rootfs/Dockerfile

@@ -32,6 +32,8 @@ COPY --from=builder /usr/local /usr/local
 COPY --from=builder /opt /opt
 COPY --from=builder /etc/nginx /etc/nginx
 
+LABEL org.opencontainers.image.source=https://github.com/kubernetes/ingress-nginx
+
 RUN apk update \
   && apk upgrade \
   && apk add -U --no-cache \

images/test-runner/rootfs/Dockerfile

@@ -125,4 +125,6 @@ RUN pip install "yamllint==$YAML_LINT_VERSION"
 # Install Yamale YAML schema validator
 RUN pip install "yamale==$YAMALE_VERSION"
 
+LABEL org.opencontainers.image.source=https://github.com/kubernetes/ingress-nginx
+
 WORKDIR $GOPATH