"Mark all as read" button should clear extension's unread notifications

[vadimdemedes]

"Mark all as read" button does not clear notifications, that were "remembered" by the extension's "Mark as unread" feature.

See #284 for "mark as unread" feature.

[AshikNesin]

I'm working on it :)

[jgierer12]

@AshikNesin can you still reproduce this? For me, local notifications get cleared along with GitHub's native ones

[AshikNesin]

@jgierer12 Just checked. The bug still exists.

[jgierer12]

My bad, I thought @vadimdemedes was talking about the checkmark button in the per-repo header

[AshikNesin]

@jgierer12 No problem 😄

Have fixed it 🔥