Retire old identifiers and point to new identifiers

[kayceesrk]

Consider the work items for the teams: https://github.com/orgs/tarides/projects/25/views/1. Some legacy work items have two ids -- a legacy id which is AAAnnn and the new id, which is the issue number. For example, "Merlin supports occurrences" has a legacy id Mer7 and a new id, which is tarides/workitems#2. It is better to retire the old id and use the new one for many reasons

1. The uniqueness of old identifiers comes from old processes (needed to be generated by Gemma and Wafae), which we no longer follow. The string names are not unique by themselves, whereas the new ids are guaranteed to be unique.
2. We don't have legacy ids for many new WIs
3. Github knows about new ids. For example, the plaintext tarides/workitems#2 is rendered as a URL. See tarides/workitems#2.

Tasks

Beta Give feedback

1. Linter should fail on old ids. Suggest new ids in the linter error message.