feat: Always try to use oAuth token when fetching git repositories

[benoitf]

What does this PR do?

Use secrets when fetching git data and initiate oAuth workflow if possible

Before, it was done only in case of private repositories
Now it will try on all public and private repositories
If there is no oAuth configured for the current SCM URL, try to fetch
with unauthenticated access

Screenshot/screencast of this PR

What issues does this PR fix or reference?

eclipse-che/che#21346

How to test this PR?

• Try to import a public project without any oAuth provider: should work as before (like a github URL)
• Setup github oAuth for example and then try to import a public project. You'll check that oAuth dialog is prompted and then we have github personal access token

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

Reviewers

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

[mshaposhnik]

Generally looks ok, only one question: will it initiate OAuth if you have GitHub configured, but trying to get the public repo?

[benoitf]

will it initiate OAuth if you have GitHub configured, but trying to get the public repo?

The workflow is the following:
if you have the secret like

apiVersion: v1
metadata:
  name: github-oauth-config
  namespace: eclipse-che
  labels:
    app.kubernetes.io/part-of: che.eclipse.org
    app.kubernetes.io/component: oauth-scm-configuration
  annotations:
    che.eclipse.org/oauth-scm-server: github

Then, trying to import a public devfile repository like https://github.com/che-samples/java-spring-petclinic/tree/devfilev2 will then throw an exception to dashboard asking to perform the oAuth workflow

Then Dashboard will prompt oAuth and a github secret (personal access token) will be added to the namespace

Then, dashboard will initiate again the same request, and as we have personal access token, it will fetch data and we'll be authenticated on the container.

So it works either on private or public repositories.

[mshaposhnik]

Ok if that's expected