Attempts to operate on locked issues/PRs

[JamesMGreene]

Locked issues/PRs cannot be commented upon without elevated user permissions. In the "Stale" Probot App, we saw that not excluding locked issues/PRs from the issues being processed led to API failure responses due to comment creation being blocked for the bot.

Easy workaround: ignore locked issues/PRs. This may not be ideal but it avoids failures and would also provide more consistent behavior with the "Stale" Probot app.