Add docker-specific info for upgrading elasticsearch #3287
Description
Our current upgrade guide gives debian, rpm, and zip/tarball upgrade instructions for upgrading self-managed clusters, but does not tell you how to upgrade using docker images / podman
Action
- Vet the linked PR with product (es delivery?) and, if it's valid, recreate it in v3 (somewhere in here), integrating it into our current upgrade guide structure
- add podman commands to pair with docker commands
see #112231 for the content that was already drafted for this in asciidoc but never merged.