Create generic error handling mechanism

[RadhaRajagopalan]

No description provided.

[nkylstad]

This seems to be working as expected!
One concern I have is the actual error message referencing our Slack as point of contact if something goes wrong - I think we need to refer our users to our servicedesk if something goes wrong rather than directly to Slack. Will investigate exactly where we should point our users and report back 😄

[mlqn]

I have also created an issue suggesting a possible solution, which would be to create a contact page listing all the ways to get in touch: #10898

[nkylstad]

That's a great idea. I suggest we look into that in the next sprint, I have not gotten any replies on who/what we should set as the contact point yet.
I think we can just remove the line about contacting us from the error message for now, and then add it when we have created a "Contact" page that we can link to.