Install cython 0.26.16 with pip

- It’s not available in conda.

Author: mgmarino

ci/deps/azure-37-numpydev.yaml

@@ -5,7 +5,6 @@ dependencies:
   - python=3.7.*
 
   # tools
-  - cython>=0.29.16
   - pytest>=5.0.1
   - pytest-xdist>=1.21
   - hypothesis>=3.58.0
@@ -15,6 +14,7 @@ dependencies:
   - pytz
   - pip
   - pip:
+    - cython>=0.29.16
     - "git+git://github.com/dateutil/dateutil.git"
     - "-f https://7933911d6844c6c53a7d-47bd50c35cd79bd838daf386af554a83.ssl.cf2.rackcdn.com"
     - "--pre"

ci/deps/azure-macos-36.yaml

@@ -5,7 +5,6 @@ dependencies:
   - python=3.6.*
 
   # tools
-  - cython>=0.29.16
   - pytest>=5.0.1
   - pytest-xdist>=1.21
   - hypothesis>=3.58.0
@@ -32,5 +31,6 @@ dependencies:
   - xlwt
   - pip
   - pip:
+    - cython>=0.29.16
     - pyreadstat
     - pyxlsb