Update Docker Run command (#756)

* Update Docker Run command

* Update Docker Run command

* Update Docker Run command

docker/HOW_TO_USE_DOCKER.md

@@ -22,6 +22,11 @@ Use the Dockerized version of AnythingLLM for a much faster and complete startup
 > If you are running another service on localhost like Chroma, LocalAi, or LMStudio
 > you will need to use http://host.docker.internal:xxxx to access the service from within
 > the docker container using AnythingLLM as `localhost:xxxx` will not resolve for the host system.
+>
+> **Requires** Docker v18.03+ on Win/Mac and 20.10+ on Linux/Ubuntu for host.docker.internal to resolve!
+>
+> _Linux_: add `--add-host=host.docker.internal:host-gateway` to docker run command for this to resolve.
+>
 > eg: Chroma host URL running on localhost:8000 on host machine needs to be http://host.docker.internal:8000
 > when used in AnythingLLM.