v3: metrics refactor
Closes #151 (closed).
Half of the metrics code (the manager) went to its own library (https://gitlab.com/elixire/drillbit), the remaining half was halved again and the first half was removed (as metrics were superseded by request metrics being tagged with more metadata), the remaining half is the request metrics code itself, and metrics that werent't superseded, such as user counts.
- Bump violet depedency as drillbit needs it
- Remove some
loop=
arguments as it's deprecated and will be removed on py3.10
Edited by luna