add managed k8s dgraph guide

[johnymontana]

No description provided.

[johnymontana]

Trying to figure out which links are failing in the mintlify broken links check. This is what I see locally, but none of these file were edited in this PR:

 ✗ mintlify broken-links
Checking for broken links...

agents/introduction.mdx
  work
  connections
  model-selection
  create-agent#build-a-new-agent-with-concierge
  /available-connections 
  
agents/knowledge-graph-extraction.mdx
  /agents/overview 
  
agents/model-selection.mdx
  /create-agent
  /connections 
  
dgraph/self-hosted.mdx
  bulk-loader/ 
  
9 broken links found.