ci: migrate python images to MCR

Type of change

• Bug Fix
• CI
• Feature

Does this introduce a change in the core logic?

• [No]

Does this introduce a change in the cloud provider implementation, if so which cloud?

• AWS
• Azure
• GCP
• IBM

Updates description?

• Updated Azure Dockerfile python image to python:3.8-slim from Microsoft Container Registry
• Copied DAG.Dockerfile to deployments/scripts/azure location and updated FROM in new Dockerfile to use python:3.8-slim image from Microsoft Container Registry (this is to avoid other cloud providers using MCR)
• Replaced apk package manager in both Dockerfiles to apt-get package manager which is available in slim tagged images
• ADO work item: Product Backlog Item 9649: Container Security for VDS Converter images

Testing

• TBD