security/py-{acme, certbot}: Update to 0.11.1

[cpm]

Summary

security/py-{acme,certbot}: Update to 0.11.1

- Update PORTVERSION and distinfo checksum (0.11.1)
- Update WWW in py-acme/pkg-descr
- Rename py-letsencrypt to py-certbot in  py-certbot/pkg-message

Test Plan

• portlint -ac output looks fine.
• poudriere testport builds fine on 10.3/i386, 10.3/amd64, 11.0/i386, 11.0/amd64, 12.0/i386 and 12.0/amd64.
• make test has passed all tests fine.