renovate PRS should be more self explanatory

We should update our renovate to add information to it's PRs

- why this PR is happening and what you should do before merging it
- we should keep up to date with dependency changes for security reasons
- but we should also be wary of updates that are from non-official repos

Also - because we suppress updates to things managed by copier template we can manage much of this by being careful about releases to copier template.
- @coretl and I discussed this and came to the conclusion that all incremental updates to copier template should be done as beta releases, except:
- if there is a critical vulnerability fix
- A periodic release, once a year or some other period to be decided