make runner.py executable

Otherwise meson will not find it.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

tests/runner.py

@@ -1,3 +1,4 @@
+#!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
 import argparse
@@ -64,7 +65,7 @@ if __name__ == '__main__':
 
     args          = parser.parse_args()
     if 'VERBOSE' in os.environ:
-        args.verbose = 2 
+        args.verbose = 2
     conf_file     = args.config_file[0]
     DEFAULT_ROOT  = os.path.abspath(os.path.dirname(conf_file))
     system_tests.set_debug_mode(args.debug)