[Checkins] [zopefoundation/Zope] dec997: Bump waitress from 1.3.1 to 1.4.0 (#747)

[Jens Vagelpohl]

  Branch: refs/heads/4.x
  Home:   https://github.com/zopefoundation/Zope
  Commit: dec99735d16dec8f0c1b0eca6a2fce3bf2c116f3
      https://github.com/zopefoundation/Zope/commit/dec99735d16dec8f0c1b0eca6a2fce3bf2c116f3
  Author: Jens Vagelpohl <jens at netz.ooo>
  Date:   2019-12-21 (Sat, 21 Dec 2019)

  Changed paths:
    M constraints.txt
    M requirements-full.txt
    M versions-prod.cfg

  Log Message:
  -----------
  Bump waitress from 1.3.1 to 1.4.0 (#747)

Bumps [waitress](https://github.com/Pylons/waitress) from 1.3.1 to 1.4.0.
- [Release notes](https://github.com/Pylons/waitress/releases)
- [Changelog](https://github.com/Pylons/waitress/blob/master/CHANGES.txt)
- [Commits](https://github.com/Pylons/waitress/compare/v1.3.1...v1.4.0)

Signed-off-by: dependabot[bot] <support at github.com>