[FEATURE]: Support linting of git-hosted notebook tasks on jobs

[asnare]

Is there an existing issue for this?

• I have searched the existing issues

Problem statement

When a job task should run a notebook, the notebook_task.source indicates whether the path is a workspace path or should be located via the git-source configured in the job settings.

Currently we always treat the path on a notebook task as a workspace paths, which fails if it's a path relative to the git-source.

Proposed Solution

• In the short-term: Notebook tasks whose path is relative to a git source should be flagged as not (yet) supported. Currently not detecting this leads to many downstream errors that are confusing and make it difficult to understand what the problem is.
  Fixed OSError: [Errno 95] bug in assess_workflows task by skipping GIT-sourced workflows from static code analysis #2924.
• In the long-term: we should support linting these as well.

Additional Context

One of the downstream errors that we currently see is attempts to download workspace paths without a leading slash (/). (Such relative paths are invalid workspace paths.)

Here is where we (currently) do not distinguish between workspace and git-source paths. (Fixed in #2924.)

[nfx]

we do support linting git repos with lint-local-code command. git integration works the way that only the owner of the git token can access the repo and no the administrator.