Update the Scala 3 migration guide for 3.3 LTS

[bishabosha]

Now with Scala 3.3.0 LTS out we need to update the migration guide to set the base recommendation to 3.3.0.

Tasks

• [ ] refutable patterns in a for comprehension generator produce a warning (use case).
• [ ] non-local returns now warn (use boundary and break)
• [ ] dropped: General Type Projections was accidentally not included in the original edition of the guide
• [ ] move the "macro library migration status" table from the old site to here

more items are likely needed to be added to the list