Update snap install instructions in README.md for network-observe plug

installation/snaps/README.md

@@ -20,6 +20,11 @@ sudo apt-get install snapd
 
 To move between different major releases,  from 2.x to 3.x  or from 3.x to 4.x,  take a look at  [snap tracks](https://forums.rocket.chat/t/introducing-snap-tracks/5890).
 
+For major release 3.x and up you might see app armor errors in your logs.  To stop that, you can connect network-observe plug for mongo db
+```text
+sudo snap connect rocketchat-server:network-observe
+```
+
 ## FAQ
 
 If you have questions about snaps best place to ask them is at the [\#ubuntu-snap](https://open.rocket.chat/channel/ubuntu-snap) channel.