Reorder metrics blocks on metrics page

[gilesdring]

Organise the grid of metrics on the metrics page.

[gilesdring]

https://data.leeds2023.co.uk/metric/

Ordering set by the order key in each index.njk file. Lower order numbers come first, then sorted by title if order is the same.

Broadly:

Signature events are order: 10 - 20
Partner and Promote are order: 30
Volunteers are order: 40
Schools: 45
Callouts: 70
Media Coverage: 80
Web Analytics: 100
Roadshow attendees: 100

Default: 10000