- `aesara.graph.opt` has been changed to `aesara.graph.rewriting.basic`
- `aesara.graph.opt_utils` has been changed to `aesara.graph.rewriting.utils`
- `aesara.graph.optdb` has been changed to `aesara.graph.rewriting.db`
- `aesara.graph.unify` has been changed to `aesara.graph.rewriting.unify`
- `aesara.graph.kanren` has been changed to `aesara.graph.rewriting.kanren`

The tests associated with each module have been updated accordingly.