Application fails to load PRs when a repo no longer exists

[ttecho]

When a repository is deleted or does not exist on github the dashboard fails to load

[Nirespire]

Desired behavior might be if one or more repos in the configuration is invalid, load all valid repo PR's and present the error header specifying which repos are invalid. Only show the blank page with the error header if the API token provided is invalid and no repos can be loaded.