debian-jessie-python => debian-stretch-python

Summary:
debian:jessie does not include an automatic way to install python3.5, which is needed by the latest version of numpy.
https://circleci.com/gh/facebookresearch/fastText/1522

adding debian:stretch test instead.

Reviewed By: EdouardGrave

Differential Revision: D17053979

fbshipit-source-id: 685a21f4996af72600b3b7444f8895a6a37cd93b

.circleci/config.yml

@@ -191,6 +191,6 @@ workflows:
       - "website-build"
       - "debian-stretch-gcc"
       - "debian-stretch-cmake"
+      - "debian-stretch-python"
       - "debian-jessie-gcc"
       - "debian-jessie-cmake"
-      - "debian-jessie-python"