ci: GHA basic format & pre-commit (#2309)

diff --git a/tests/test_eval_call.py b/tests/test_eval_call.py
index 53c7e72..d42a0a6 100644
--- a/tests/test_eval_call.py
+++ b/tests/test_eval_call.py
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 # This file is called from 'test_eval.py'
 
 if 'call_test2' in locals():