Print the name of faulty jinja templates in pre-commit (#11484)

tests/scripts/check-templates.py

@@ -1,9 +1,20 @@
 #!/usr/bin/env python
 
 import sys
+import traceback
 from jinja2 import Environment
+from jinja2.exceptions import TemplateSyntaxError
+
 
 env = Environment()
+errors = False
 for template in sys.argv[1:]:
+    try:
         with open(template) as t:
             env.parse(t.read())
+    except TemplateSyntaxError as e:
+        print (template)
+        traceback.print_exc()
+        errors = True
+if errors:
+    exit (1)