CI: Conda 4.14 with python 3.9 broke docker build

[phofl]

It looks like condo 4.14 broke our docker build (when installed for python 3.9). It seems that downgrading to 4.14 with python 3.8 breaks something with the certificates. Pinning to 4.13 for the 3.9 version fixed this.

https://github.com/pandas-dev/pandas/runs/7906649660?check_suite_focus=true

#48139

[tomaarsen]

Same issue here. I appreciate the heads up for a fix.