gunittest: add missing key to format error message (fix for https://trac.osgeo.org/grass/changeset/64662)

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@64679 15284696-431f-4ddb-bdfa-cd5b030d7da7

lib/python/gunittest/main.py

@@ -154,7 +154,7 @@ def main():
     if not os.path.exists(os.path.join(gisdbase, location)):
         sys.stderr.write("GRASS Location <{loc}>"
                          " does not exist in GRASS Database <{db}>\n".format(
-                             location, gisdbase))
+                             loc=location, db=gisdbase))
         sys.exit(1)
     results_dir = args.output
     silent_rmtree(results_dir)  # TODO: too brute force?