InfluxDB 2: Deleting not exists label or label with not exists resource should produce `404 Not Found` response

[bednar]

It's should works for all types of resource:

• Dashboards
• Notifications
• Checks
• TelegrafConfigs
• NotificationRules
• Buckets
• Variables
• Tasks
• ...

# Delete label for not exists resource
--> DELETE http://127.0.0.1:9999/api/v2/buckets/ffffffffffffffff/labels/ffffffffffffffff

<-- 204 No Content http://127.0.0.1:9999/api/v2/buckets/ffffffffffffffff/labels/ffffffffffffffff 

Expected behavior:
Produce 404 HTTP response.

Actual behavior:
Produce 204 No Content HTTP response.

Environment info:

• InfluxDB version: latest nightly build

cc @AlirieGray

[glinton]

Seems that a 204 is the appropriate response here as deletes should be idempotent. I would expect a GET returns a 404, but i would expect multiple DELETE calls to the same resource to return that it was deleted (in this case a 204), unless it failed for some reason (401, 5XX, etc...)