PEP8 have new changes that make invalid escapes a hard failure.
Also, it's failing on the requirements check.
Also the build-openstack-releasenotes job taker the setup info
from master, as we do not have master anymore we can not run the
build-openstack-releasenotes job.
This submission fixes:
- Unit tests failing with scaping incorrectly backslashes.
- Lower constraints.
- Requirements.
- Test requirements.
Closes-Bug: 1805583
Change-Id: I3a620ca13eaf7ca0e8d1e560ffeb30d25f4d82c5