feature: docker: add image source label to dockerfiles (#419)

To get changelogs shown with Renovate a docker container has to add the source label described in the OCI Image Format Specification.

For reference: https://github.com/renovatebot/renovate/blob/main/lib/modules/datasource/docker/readme.md

docker/Dockerfile

@@ -1,5 +1,6 @@
 FROM node:lts-bookworm
 LABEL maintainer="Coderaiser"
+LABEL org.opencontainers.image.source="https://github.com/coderaiser/cloudcmd"
 
 RUN mkdir -p /usr/src/app
 WORKDIR /usr/src/app