Handle Github discussion notification

[ymgyt]

Is your feature request related to a problem? Please describe.

Currently, selecting a discussion notification redirects to the discussion list. Since the web UI allows direct navigation to the notified discussion, we would like to implement the same behavior.

Describe the solution you'd like

The notification response only includes the discussion title. Therefore, it is necessary to use the discussion API to search for the discussion ID based on the title.

https://docs.github.com/en/graphql/guides/using-the-graphql-api-for-discussions

Additional context

• It seems that only a GraphQL API is supported for discussions
• There doesn't seem to be a REST API available.