Mattermost-plugin-github: When using a label-filter subscription, two posts are made when an issue is created with this label

[mickmister]

For a subscription such as /github subscriptions add mattermost issues,label:"Triage", any new issues cause a post to be made in the channel. There is a second post that occurs at the same time if the label would match Triage.

Now that we show the labels on the "new issue" posts, we should avoid creating the "label-added" posts during the processing of the new issue. Only the "new issue" post should be made. This probably occurs with PRs as well.

[mickmister]

If GitHub sends a separate issue-labeled event when the issue is created with a label, we can check if the issue was created within the last 2 seconds or something like that, in order to avoid the extra post.

[EnzoBtv]

Hey @mickmister @hanzei I'm looking for issues to colaborate. Can I get this one?

[mickmister]

Thanks @EnzoBtv!!