Remove reliance on entrypoint as a string to install postgis.
Remove reliance on entrypoint as a string to install postgis.

Turns out that the entrypoint script for postgres container is smart
enough to only initialize the database if we call it with the command 'postgres'.

datawagovau/datacats,datawagovau/datacats,JJediny/datacats,reneenoble/datacats,wardi/datacats,poguez/datacats,JackMc/datacats,deniszgonjanin/datacats,florianm/datacats,deniszgonjanin/datacats,poguez/datacats,datacats/datacats,dborzov/datacats,JJediny/datacats,JackMc/datacats,datacats/datacats,florianm/datacats,reneenoble/datacats,wardi/datacats,dborzov/datacats