AlertManager does not start in docker properly

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2

I just found it changing the alertmanager config file to:

global:

receivers:
  - name: default-receiver
  - name: alertsnitch
    webhook_configs:
      - url: http://host.docker.internal:9567/webhook

# We want to send all alerts to alertsnitch and then continue to the
# appropiate handler.
route:
  group_wait: 10s
  group_interval: 5m
  receiver: default-receiver
  repeat_interval: 3h
  
  routes:
    - receiver: alertsnitch
      continue: true