show error message when service account is missing (hence revision will not be created)

[cppforlife]

knctl got stuck waiting for new revision because service account did not exist, hence Configuration wasnt updated, hence Revision will never be created.

$ knctl service show -s simple-app2
Service 'simple-app2'

Name             simple-app2
Domain           simple-app2.default.example.com
Internal Domain  simple-app2.default.svc.cluster.local
Annotations      -
Age              2m

Service 'simple-app2' conditions

Type                 Status  Age  Reason           Message
ConfigurationsReady  False   2m   RevisionFailed   Revision creation failed with message: "Internal error occurred: admission
                                                   webhook \"webhook.build.knative.dev\" denied the request: mutation failed:
                                                   serviceaccounts \"serv-acct1\" not found".
Ready                False   1s   RevisionMissing  Configuration "simple-app2" does not have any ready Revision.
RoutesReady          False   2m   RevisionMissing  Configuration "simple-app2" does not have any ready Revision.

Pods conditions

Pod  Type  Status  Age  Reason  Message

Succeeded

[drnic]

I've created an upstream Build issue so perhaps we can get status updates with error messages knative/build#471

[drnic]

The same category of issue occurs if --template buildpack references a BuildTemplate that doesn't exist yet. It only appears in build-controller logs:

knative-build/build-controller-79d6cc9d57-7svtq[build-controller]: {"level":"error","logger":"controller.build-controller","caller":"build/build.go:141","msg":"Failed to validate build: buildtemplates.build.knative.dev \"buildpack\" not found","knative.dev/controller":"controller","knative.dev/controller"