Add ability to show a warning banner by configuring CheCluster CR (#466)

[ibuziuk]

Backporting eclipse-che/che#20724 to 7.42.x

PR contains a number of commits to make the warning header functionality work as expected. Verified against the che-dev dogfooding instance:

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Docker image build succeeded: quay.io/eclipse/che-dashboard:pr-478

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This pull-request has been approved by: akurinnoy, ibuziuk, olexii4

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[github-actions]

Docker image build succeeded: quay.io/eclipse/che-dashboard:pr-478

[ibuziuk]

@olexii4 thanks for the review, just wondering about the removal of the packages/dashboard-backend/src/services/kubeclient/keycloak.ts will it affect the che-server-based setup / CRW 2.15.3? I verified only against che-dev cluster with DevWorkspace engine enabled by default and spinning the cluster bot with CRW 2.15.2 atm to make sure that it will work as expected.

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New changes are detected. LGTM label has been removed.

[github-actions]

Docker image build succeeded: quay.io/eclipse/che-dashboard:pr-478

[nickboldt]

Yikes, that's a lot of changes. Some seem unrelated... like removing stuff about keycloak?

[nickboldt]

Where is the displayed message & link configured? I scrolled the whole PR but got lost in a typescript haze, didn't see any mention of a blog post or whatnot.

[ibuziuk]

the message will be configured on the codeready-worskapces-operator defaults for spec.dashboard.warning

[nickboldt]

We can add / change annotations in https://github.com/redhat-developer/devspaces-images/blob/devspaces-3-rhel-8/codeready-workspaces-operator/build/scripts/sync-che-operator-to-crw-operator.sh#L249-L258 when transforming upstream Che Operator into Dev Spaces Operator

Once you have a sample bit o' text to inject there, please throw me a PR for the above repo and we can verify it's appearing in DS 3 (but not in Che 7.44)

[ibuziuk]

@nickboldt the PR for the operator has been merged - eclipse-che/che-operator#1339
from the downstream operator perspective please provide the default value for spec.dashboard.warning it could be lorem ipsum for now

[olexii4]

@ibuziuk I have returned packages/dashboard-backend/src/services/kubeclient/keycloak.ts back(commit).

[github-actions]

Docker image build succeeded: quay.io/eclipse/che-dashboard:pr-478