Please Improve Documentation for Stack Deploy --resolve-image

[phil-vuollet-anterdit]

File: engine/reference/commandline/stack_deploy.md

The options for docker stack deploy --resolve-image are not clearly defined. They are merely listed. Overall, resolve-image option is not descriptive enough.

see: https://stackoverflow.com/questions/67268839/what-does-option-resolve-image-in-docker-stack-mean-exactly