Update index.md

Author: agiudiceandrea

docs/index.md

@@ -38,7 +38,7 @@ This plugin can be installed using the QGIS Plugin Manager.
 
 - This plugin runs only with QGIS 3.x and Python 3.
 - pgRouting v3.x up and running to use this plugin.
-- Additionally, QGIS needs python-psycopg2 installed to be able to connect to the database.
+- Additionally, QGIS needs python3-psycopg2 installed to be able to connect to the database.
 
 ## Links