feat(db): support postgresql database (#3643)

Co-authored-by: Meier Lukas <meierschlumpf@gmail.com>

.env.example

@@ -34,6 +34,10 @@ DB_URL='FULL_PATH_TO_YOUR_SQLITE_DB_FILE'
 # DB_PASSWORD='password'
 # DB_NAME='name-of-database'
 
+# The following is an example on how to use the node-postgres driver:
+# DB_DRIVER='node-postgres'
+# DB_URL='postgres://user:password@host:port/database'
+
 # The below path can be used to store trusted certificates, it is not required and can be left empty.
 # If it is empty, it will default to `/appdata/trusted-certificates` in production.
 # If it is used, please use the full path to the directory where the certificates are stored.