The missing-injectable migration has been updated to handle a breaking change that is
unrelated to missing ´@Injectable` decorators. Though, the breaking change will be handled
as part of this migration since we did not want to create another migration (with all the boilerplate etc.)
The guide has been already updated to reflect the new pattern the migration handles, but we
should also rename the title of the guide to something that also mentions the other pattern.
Not renaming the guide URL since it is referenced in past releases and it's safer to keep the old
URL. The important thing is to change the actual rendered title.
PR Close#34125
Since we created the migration guide for the `missing-injectable` schematic, the schematic
changed in various ways. e.g. the migration no longer migrates classes passed to `useExisting`
Additionally the migration has been expanded to handle another Ivy breaking change where
providers like `{provide: X}` will be intepreted as `{provide: X, useClass: X}`. This pattern should
be documented in the migration guide.
PR Close#33960
