fix README typo

README.md

@@ -6,7 +6,7 @@ Passion Postgres + PostGis
 
 * Download the ban address database as a CSV
     ```bash
-    makdir -p data
+    mkdir -p data
     wget -O data/adresses-france.csv.gz https://adresse.data.gouv.fr/data/ban/adresses/latest/csv/adresses-france.csv.gz
     ```