O365 connectors within Teams will be deprecated

[firefart]

Just a follow up issue to track atc0005/go-teams-notify#262 as MS deprecated office connectors and you now need to use workflows.
Once the library is updated, we need to pull it in to this repo to ensure teams webhooks keep working

[nikoksr]

Thanks a lot for reaching out, @firefart! I've opened a new issue that I encountered while trying to fix this. Will close this here issue once everything has been resolved.