Auto generated issues made from unresolved MR discussions

When you create auto generated issues from unresolved MR discussions, we include the text "Follow-up from 'Title'". The user has the option to change the text, but if they don't we can end up with lists that look like this:

This makes it difficult to sort through the different issues.

We should add part of the first line of the discussion to the issue title in order to help differentiate between different issues that are created via an MR discussion.

Limit characters of both portions to around 50chars so titles don't get too long. Example:

Follow-up from Asperiores eum rerum dicta consequatur consequuntu...: Asperiores eum rerum dicta consequatur consequuntu...