Maintainer status = write access instead of triage access?

[vidartf]

Currently it seems like the decision for whether to put something in the Maintainer column seem incorrect. E.g. if I filter on the JupyterLab board to the Lumino repo, I see my PR listed under the Maintainer column, but I don't have maintainer rights on that repo (at least I don't have merge rights).

[jasongrout]

In #15, I added explicit checks about what permission levels a "maintainer" has. Right now it is triage or above. We could keep it as-is, bump it to write or above, or separately track engagement by the two groups. I'm not sure which is more valuable.

[jasongrout]

Since the current code does look at the permission per repository, I changed the title to reflect the underlying issue here, i.e., that we are scoping to triage access instead of write access.

[yuvipanda]

Fixed by #54