add to dashboard bugs

[camerondeleone]

Bug description

There are a couple related bugs here.

1. This path results in unexpected results: Add insight to dashboard, click into dashboard to edit (switch from funnel to trend), save insight --> results not updated on dashboard even though they are reflected when viewing individual insight)
2. Clicking into recently edited insight above and adding to dash, I accidentally added it to a dashboard I didn't want to (first on the list, "The Survey"), but then could not remove it. Looks like I may not have permission to do this, but was able to add something via the 'add to dashboard' route from the individual insight regardless.

How to reproduce

First issue:

1. Create an insight and add to dashboard
2. click through from dash to 'edit' and change the insight type, then save
3. view that in dash - it's not updated

Second issue:

1. on an insight, click add to dashboard and select one you don't have edit permission on
2. you should be able to add the insight from this route, but then cannot remove it
3. Here is a culprit insight and dash (and please remove if you have permission)

Here is a quick video https://posthog.slack.com/archives/C01RJ7T212S/p1657708603632139

Environment

• PostHog Cloud
• self-hosted PostHog (ClickHouse-based), version/commit: please provide
• self-hosted PostHog (Postgres-based, legacy), version/commit: please provide

Additional context

Thank you for your bug report – we love squashing them!

[pauldambra]

One part of this is in #10791. We weren't checking that someone had permission on a dashboard before adding an insight to it. But operations after that then took account of the new permissions. So we can fix that...

But you're a staff/admin user so the next question is whether you should still have had permissions after adding the insight...

[pauldambra]

2 is fixed. 1 is a duplicate of #10263