[Bexley] Add form for properties with no collections

[chrismytton]

Makes some changes to the enquiry form to allow properties with no collections to report a missed collection via email to one of two categories.

• Removes the check for a valid service in the enquiry sub in the Waste controller, think this is ok, as nothing breaks if there isn't a service, it just isn't recorded if it's missing.
• Adds support for checkboxes in extra data on enquiry categories
• Changes to support enquiry checkboxes
• Changes to support service no longer being required

For https://3.basecamp.com/4020879/buckets/35109031/todos/7182401179

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 90.00000% with 2 lines in your changes missing coverage. Please review.

Project coverage is 82.63%. Comparing base (616c0e5) to head (036cc36).

Files	Patch %	Lines
perllib/FixMyStreet/Cobrand/Bexley/Waste.pm	83.33%	1 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #4995 +/- ## ========================================== + Coverage 82.60% 82.63% +0.02% ========================================== Files 393 393 Lines 30770 30786 +16 Branches 4881 4882 +1 ========================================== + Hits 25419 25440 +21 + Misses 3900 3898 -2 + Partials 1451 1448 -3 ```

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