Bump waitress from 1.1.0 to 1.4.0

Bumps [waitress](https://github.com/Pylons/waitress) from 1.1.0 to 1.4.0.
- [Release notes](https://github.com/Pylons/waitress/releases)
- [Changelog](https://github.com/Pylons/waitress/blob/master/CHANGES.txt)
- [Commits](Pylons/waitress@v1.1.0...v1.4.0)

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

requirements.txt

@@ -3,7 +3,7 @@ SQLAlchemy>=1.3.0
 alembic==1.0.0
 pyramid_mako==1.0.2
 zope.sqlalchemy==1.0
-waitress==1.1.0
+waitress==1.4.0
 pastedeploy>=2.0
 paste>=2.0
 psycopg2-binary==2.7.5