[Bug] instanceSelector.matchExpressions not working for GrafanaDatasource about grafana-operator

[NissesSenap]

Thanks for a well described issue @sebbbastien .
I have tried this out and I can verify that I get the same issue.
I also gave the following config a try instead.

apiVersion: grafana.integreatly.org/v1beta1
kind: Grafana
metadata:
  name: grafana-production
  labels:
    dashboards: lalal
spec:
  config:
    auth:
      disable_login_form: "false"
---
apiVersion: grafana.integreatly.org/v1beta1
kind: Grafana
metadata:
  name: grafana-staging
  labels:
    dashboards: grafana
spec:
  config:
    auth:
      disable_login_form: "false"
---
apiVersion: grafana.integreatly.org/v1beta1
kind: GrafanaDatasource
metadata:
  name: example-grafana-datasource
spec:
  instanceSelector:
    matchLabels:
      dashboards: grafana
  datasource:
    name: "Loki datasource"
    type: loki
    url: http://loki-gateway.loki.svc.cluster.local
    access: proxy
    database: loki
    editable: false
    isDefault: true
---
apiVersion: grafana.integreatly.org/v1beta1
kind: GrafanaDatasource
metadata:
  name: example-grafana-datasource-hidden
spec:
  instanceSelector:
    matchLabels:
      dashboards: grafana
  datasource:
    name: "Loki datasource hidden"
    type: loki
    url: http://loki-gateway.loki.svc.cluster.local
    access: proxy
    database: loki
    editable: false
    isDefault: true

So I used matchLabels instead.

  instanceSelector:
    matchLabels:
      dashboards: grafana

And then I didn't get the same issue. So in the meantime, I would suggest using this solution.