fix the python 3.7 limitations inside circleci tests

Author: shlomiku

.circleci/config.yml

@@ -58,6 +58,7 @@ jobs:
       - run:
           name: run tests
           command: |
+            pip install pandas<1.2.0 numpy<1.20.0
             python setup.py install
             pip install flake8 && flake8 alpaca_trade_api tests
             python setup.py test

requirements/requirements.txt

@@ -1,6 +1,6 @@
-pandas<1.2.0  # this package requires python 3.7 for higher versions
-numpy<1.20.0  # this package requires python 3.7 for higher versions
+pandas
+numpy
 requests>2,<3
-urllib3>1.24,<1.26
+urllib3>1.24,<2
 websocket-client>=0.56.0,<1
 websockets>=8.0,<9