Bump certifi from 2019.3.9 to 2019.11.28 in /requirements (from PR #466)
Bump certifi from 2019.3.9 to 2019.11.28 in /requirements (from PR #466)

Bumps [certifi](https://certifi.io/) from 2019.3.9 to 2019.11.28.

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>

glogiotatidis/basket,glogiotatidis/basket,glogiotatidis/basket