Update Stack default version to 8.1.0

[endorama]

This PR supersede #708 and updates default Stack version to 8.1.0 to align with latest release.

[elasticmachine]

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• Start Time: 2022-03-10T09:47:15.229+0000

• Duration: 17 min 26 sec

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[mtojek]

@endorama Could you please iterate on this and missing Kubernetes fields:

[1] field "kubernetes.namespace_uid" is undefined
[2] field "kubernetes.node.labels.beta_kubernetes_io/arch" is undefined
[3] field "kubernetes.node.labels.beta_kubernetes_io/os" is undefined
[4] field "kubernetes.node.labels.kubernetes_io/arch" is undefined
[5] field "kubernetes.node.labels.kubernetes_io/hostname" is undefined
[6] field "kubernetes.node.labels.kubernetes_io/os" is undefined
[7] field "kubernetes.node.labels.node-role_kubernetes_io/control-plane" is undefined
[8] field "kubernetes.node.labels.node-role_kubernetes_io/master" is undefined
[9] field "kubernetes.node.labels.node_kubernetes_io/exclude-from-external-load-balancers" is undefined

I guess you will find them in the elastic/integrations repository.

[endorama]

The failure is coming from kubernetes packages:

one or more errors found in documents stored in metrics-kubernetes.pod-ep data stream: [0] field "kubernetes.namespace_labels.kubernetes_io/metadata_name" is undefined
[1] field "kubernetes.namespace_uid" is undefined
[2] field "kubernetes.node.labels.beta_kubernetes_io/arch" is undefined
[3] field "kubernetes.node.labels.beta_kubernetes_io/os" is undefined
[4] field "kubernetes.node.labels.kubernetes_io/arch" is undefined
[5] field "kubernetes.node.labels.kubernetes_io/hostname" is undefined
[6] field "kubernetes.node.labels.kubernetes_io/os" is undefined
[7] field "kubernetes.node.labels.node-role_kubernetes_io/control-plane" is undefined
[8] field "kubernetes.node.labels.node-role_kubernetes_io/master" is undefined
[9] field "kubernetes.node.labels.node_kubernetes_io/exclude-from-external-load-balancers" is undefined
[10] field "kubernetes.node.uid" is undefined

[mtojek]

@endorama I kindly asked you to adjust the kubernetes package here.

[endorama]

GitHub cache hit again 😓 I'm on it