When Dependabot fails to update a package but still creates PR, mark as warning instead of error

[Ossiam]

Usually an error indicates that something has gone wrong and should be fixed. But currently when the Dependabot extension fails to update a package, it still creates a PR with the successful package updates. In my opinion it's misleading when in that case it displays as failure in the pipeline.
Example:

I feel a warning would be more appropriate in these cases, instead of error

[rhyskoedijk]

@Ossiam, this will be improved by #1608