docs: add note for increased build time

docs/troubleshooting.rst

@@ -201,4 +201,7 @@ This issue can occur due to problems with your network while cloning edx-platfor
 
 You should first of all try to rerun the command you were trying to run to see if it works.
 
-If that does not work, you can follow the tutorial above for `High resource consumption <#high-resource-consumption-on-tutor-images-build-by-docker>`_ and set `max-parallelism = 1` so that while edx-platform is being cloned, the network is not being utilized by another command.
+If that does not work, you can follow the tutorial above for `High resource consumption <#high-resource-consumption-on-tutor-images-build-by-docker>`_ and set `max-parallelism = 1` so that while edx-platform is being cloned, the network is not being utilized by another command.
+
+.. note::	
+	The build time for the image will be considerably slow now as each step will be built one by one.