feat: Support OpenShift external IDP

[tolusha]

What does this PR do?

Support OpenShift external IDP

Screenshot/screencast of this PR

N/A

What issues does this PR fix or reference?

https://issues.redhat.com/browse/CRW-9763

How to test this PR?

eclipse-che/che-docs#3024

PR Checklist

As the author of this Pull Request I made sure that:

• The Eclipse Contributor Agreement is valid
• Code produced is complete
• Code builds without errors
• Tests are covering the bugfix
• The repository devfile is up to date and works
• Sections What issues does this PR fix or reference and How to test this PR completed
• Relevant user documentation updated
• Relevant contributing documentation updated
• CI/CD changes implemented, documented and communicated

Release Notes

N/A

Reviewers

Reviewers, please comment how you tested the PR when approving it.

[openshift-ci]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[tolusha]

/retest

[vinokurig]

Please try to avoid wildcard imports

[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: tolusha, vinokurig

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[openshift-ci]

New changes are detected. LGTM label has been removed.

[openshift-ci]

@tolusha: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/v19-github-no-pat-oauth-flow	d9bca49	link	true	/test v19-github-no-pat-oauth-flow
ci/prow/v19-github-no-pat-oauth-flow-ssh-url	d9bca49	link	true	/test v19-github-no-pat-oauth-flow-ssh-url
ci/prow/v19-azure-no-pat-oauth-flow-raw-devfile-url	d9bca49	link	true	/test v19-azure-no-pat-oauth-flow-raw-devfile-url
ci/prow/v19-bitbucket-no-pat-oauth-flow	d9bca49	link	true	/test v19-bitbucket-no-pat-oauth-flow
ci/prow/v19-gitlab-with-pat-setup-flow	d9bca49	link	true	/test v19-gitlab-with-pat-setup-flow

Full PR test history. Your PR dashboard.

Details

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