fix clean/create in pgdump/restore (#1457)

tests/README.md

@@ -329,6 +329,9 @@ You can however easily test with a different engine.
 
 Run Postgres somewhere, version 10 or above - easy to do in a docker container.
 
+You also need to install a postgresql-client package or equivalent, to provide
+recent pg_dump and pg_restore executables (not older than the PG version in the docker container).
+
 ```
 $ sudo docker run --detach --name=postgres -p 5432:5432 --env="POSTGRES_PASSWORD=postgres" postgres:latest
 ```
@@ -373,6 +376,8 @@ or for MariaDB
 $ sudo docker run --cap-add=sys_nice --detach --name=mariadb -p 3306:3306  --env="MYSQL_ROOT_PASSWORD=password" mariadb
 ```
 
+A mysql-client package is required as well.
+
 ## gotchas
 
  - Testing with Postgres or MySQL/MariaDB leads to (unpredictably) failing

tests/lib/db/instance-postgres

@@ -50,7 +50,7 @@ setup() {
 
 dump() {
     backup_file="${1?Missing file to backup database to}"
-    pg_dump -Ft --dbname crowdsec_test --file "$backup_file"
+    pg_dump -Ft --dbname crowdsec_test --clean --create --file "$backup_file"
 }
 
 restore() {