[Camden] Setup Confirm integration

[MorayMySoc]

Adds necessary Confirm roles https://github.com/mysociety/societyworks/issues/4298
Fixes https://github.com/mysociety/societyworks/issues/4504

[skip changelog]

[codecov]

Codecov Report

Attention: Patch coverage is 71.42857% with 4 lines in your changes missing coverage. Please review.

Project coverage is 82.64%. Comparing base (1173010) to head (075bed2).
Report is 5 commits behind head on master.

Files with missing lines	Patch %	Lines
perllib/FixMyStreet/Cobrand/Camden.pm	71.42%	2 Missing and 2 partials ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4999   +/-   ##
=======================================
  Coverage   82.64%   82.64%           
=======================================
  Files         404      404           
  Lines       31501    31513   +12     
  Branches     4993     4998    +5     
=======================================
+ Hits        26034    26045   +11     
+ Misses       3985     3984    -1     
- Partials     1482     1484    +2     

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[dracos]

To note, from discussion in Slack today, this doesn't work because Camden.pm has an open311_update_missing_data which is overriding the one from ConfirmOpen311. And open311_config can presumably be removed from Camden.pm.

[dracos]

I've reviewed/squashed in your fixup commit, and then added a new commit on top, which I can't ask for review as it's your PR but if you could review it, thanks :)

[MorayMySoc]

Thanks - changes look good to me!