CI: Pin CPython to 3.6.6 (#23322)

TomAugspurger · web-flow · commit 1c26375c0743 · 2018-10-24T13:50:01.000-05:00
diff --git a/ci/azure-windows-36.yaml b/ci/azure-windows-36.yaml
@@ -16,7 +16,7 @@ dependencies:
   - pyarrow
   - pytables
   - python-dateutil
-  - python=3.6.*
+  - python=3.6.6
   - pytz
   - scipy
   - thrift=0.10*
