+1 example to append_conf()

Author: funbringer

Diff for: testgres/node.py

@@ -533,6 +533,7 @@ def append_conf(self, line='', filename=PG_CONF_FILE, **kwargs):
         Examples:
             append_conf(fsync=False)
             append_conf('log_connections = yes')
+            append_conf(random_page_cost=1.5, fsync=True, ...)
             append_conf('postgresql.conf', 'synchronous_commit = off')
         """