Recreating the intetion of PR #1816 explaining "make not found error" (…

…#1995)

docs/installation/docker-troubleshooting.md

@@ -1,5 +1,9 @@
 # Troubleshooting
 
+### Make command not found
+
+If you get the error `bash: make: command not found` then you need to install GNU make. Run `sudo apt update` and `sudo apt install make` to install.
+
 ### Docker Versions
 
 If you get an error such as: `ERROR: Version in "./docker-compose.activemq.yml" is unsupported.`, then you need to upgrade Docker. Enter the command `make clean` before re-attempting to `make demo`.
@@ -20,6 +24,6 @@ If you are using Docker Desktop for Mac, and get timeout errors when spinning up
 ERROR: for isle-dc_mariadb_1  UnixHTTPConnectionPool(host='localhost', port=None): Read timed out. (read timeout=480)
 ```
 
-you can try quitting Docker completely (make sure there is no whale icon in your top toolbar - may need to select "Quit" from the whale icon itself) and then restart Docker. 
+you can try quitting Docker completely (make sure there is no whale icon in your top toolbar - may need to select "Quit" from the whale icon itself) and then restart Docker.
 ### 504 Bad Gateway
 If you get a white screen with a 504 Bad Gateway error, this means your containers haven't finished initializing themselves yet.  If you've waiting an appropriate amount of time (2-5 minutes), then there is most likely an error in a container's startup script.  Use `docker ps -a` to see which services have `Exited` status, and then tail their logs with `docker-compose logs service_name`.