Invalid error Map keys must be uniqueYAML on mutliple merges

[AlexisColes]

Describe the bug

dind: &dind
  image: 116661453557.dkr.ecr.eu-west-1.amazonaws.com/github-actions-runner-dind:15
  container_mode: false
  dindMode: true

c-2: &c2
  resources: 
    requests:
      cpu: 2
      memory: 4Gi
      
runners:
  c-2-dind:
    <<: *dind
    <<: *c2
    min_replicas: 2

This is valid yaml!

however the line <<: *c2 is marked as an error "Map keys must be uniqueYAML on mutliple merges"

Expected Behavior

It should not flag this as an error.

Current Behavior

If flags it as an error

Steps to Reproduce

1. put the above yaml into vscode with this extension loaded.

Environment

• [ ] Windows
• [ ] Mac
• [x] Linux
• [ ] other (please specify)