Add docker image address

Author: theredrad

README.md

@@ -22,4 +22,9 @@ The backend of https://lorem.space lives here.
 * `min-width`: minimum supported width (integer)
 * `max-width`: maximum supported width (integer)
 * `min-height`: minimum supported height (integer)
-* `max-height`: maximum supported height (integer)
+* `max-height`: maximum supported height (integer)
+
+### Docker
+You can pull & run the public docker image from github package registry:
+
+`$ docker pull ghcr.io/manasky/lorem-server:latest`