Publish docling-serve images to ghcr and quay container repositories

[vishnoianil]

This commit:

• Creates container file to build the image for cpu only and default "with gpu" images
• Adds workflow jobs to publish the images to ghcr.io and quay.io
• Makefile to build these images locally for linux/amd64 platform.

[vishnoianil]

Pending:

• [x] local build for both mode
• [x] possible image optimization

[vishnoianil]

The size of cpu only image is around 3.5G and with GPU dependency it's around 7.5G.

[vishnoianil]

@dolfim-ibm PTAL and let me know if you have thoughts.