Initially the plan was to have a migration that adds `@Injectable()` to
all pipes in a CLI project so that the pipes can be injected in Ivy
similarly to how it worked in view engine.
Due to the planned refactorings which ensure that `@Directive`, `@Component`
and `@Pipe` also have a factory definition, this migration is no longer
needed for Ivy. Additionally since it is already disabled (due to
572b54967c) and we have a more generic
migration (known as `missing-injectable)` that could do the same as
`injectable-pipe`, we remove the migration from the code-base.
PR Close#32184
639b732024