Synced from eclipse/che issue

https://github.com/eclipse/che/issues/21997

Is your enhancement related to a problem? Please describe

If I try to start a workspace from a private repository but OAuth is not supported (e.g. the repo is AzureDevOps) and I get the following error:

Error occurred during creation a workspace from devfile located at `<repo-url>`. Cause: Neither of `apiVersion` or `schemaVersion` found. This is not a valid devfile.

The message is confusing because it looks like Che was able to retrieve a Devfile but it was invalid.
And it's not possible to start the workspace although

Describe the solution you'd like

The message should rather be something like:

::Warning::
Looking for a Devfile in the git repository failed. The git server API may not supported by Eclipse Che (or the git server hasn't been configured appropriately).

Note that the git cloning of the repository will succeed if it's public or it's private and the developer git credentials secret has been configured.

Click to continue

Additional context

<img width="2014" alt="image" src="https://user-images.githubusercontent.com/606959/218342904-1b8ff103-b8da-4ca2-8b87-09a9576c34c1.png">