Install shellcheck with apt in vagrant

[pmalek-sumo]

It seems that it isn't as easy as we might think:
shellcheck's snap doesn't have access to all filesystems

snap connections shellcheck
Interface        Plug                        Slot   Notes
home             shellcheck:home             :home  -
removable-media  shellcheck:removable-media  -      -

and it doesn't seem that it's easy to allow it to access (in our case) /sumologic

https://askubuntu.com/questions/1033344/how-to-give-snaps-access-to-somedir

Testing performed

• ci/build.sh
• Redeploy fluentd and fluentd-events pods
• Confirm events, logs, and metrics are coming in

[sumo-drosiek]

😕