Move Kubernetes and Prometheus integration to Settings -> Operations
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### Problem to solve
Make "operations" (Sentry, Kubernetes, Prometheus, etc) integrations all configurable from the same place.
### Intended users
Developer
### Further details
Make it easier to find operation integration settings and configuration.
### Proposal
Move the Kubernetes and Prometheus integration settings from "Settings -> Integrations" to ""Settings -> Operations".
The "Operations" menu contains Metrics, Environments, Error Tracking, Serverless and Kubernetes. If I go to "Settings -> Operations", I assume that I could configure all of these services, but I can only configure "Error Tracking"
### Permissions and Security
N/A
### Documentation
Update documentation with the integrations mentioned.
### Testing
Not sure
### What does success look like, and how can we measure that?
Moved menu items.
### Links / references
issue