Log Message:
net/py-{acme,certbot}: Update to 0.26.0.

### Added

- A new security enhancement which we're calling AutoHSTS has been
  added to Certbot's Apache plugin. This enhancement configures your
  webserver to send a HTTP Strict Transport Security header with a low
  max-age value that is slowly increased over time. The max-age value is
  not increased to a large value until you've successfully managed to
  renew your certificate. This enhancement can be requested with the
  --auto-hsts flag.
- New official DNS plugins have been created for Gehirn Infrastracture
  Service, Linode, OVH, and Sakura Cloud. These plugins can be found
  on our Docker Hub page at https://hub.docker.com/u/certbot and on
  PyPI.
- The ability to reuse ACME accounts from Let's Encrypt's ACMEv1
  endpoint on Let's Encrypt's ACMEv2 endpoint has been added.
- Certbot and its components now support Python 3.7.
- Certbot's install subcommand now allows you to interactively choose
  which certificate to install from the list of certificates managed
  by Certbot.
- Certbot now accepts the flag `--no-autorenew` which causes any
  obtained certificates to not be automatically renewed when it
  approaches expiration.
- Support for parsing the TLS-ALPN-01 challenge has been added back to
  the acme library.

### Changed

- Certbot's default ACME server has been changed to Let's Encrypt's
  ACMEv2 endpoint. By default, this server will now be used for both
  new certificate lineages and renewals.
- The Nginx plugin is no longer marked labeled as an "Alpha" version.
- The `prepare` method of Certbot's plugins is no longer called before
  running "Updater" enhancements that are run on every invocation of
  `certbot renew`.