Update pandas from 0.23.4 to 0.24.2

Author: pyup-bot

requirements.txt

@@ -8,7 +8,7 @@ cssselect==1.0.3
 idna==2.8
 lxml==4.3.0
 numpy==1.16.0
-pandas==0.23.4
+pandas==0.24.2
 pyquery==1.4.0
 python-dateutil==2.7.5
 pytz==2018.9