trivial: add pylint disable comment for exec-used (#52732)

pylint.rc

@@ -17,7 +17,6 @@ disable=
     disallowed-name,
     duplicate-code,
     eval-used,
-    exec-used,
     fixme,
     global-variable-undefined,
     import-outside-toplevel,

wcs/settings.py

@@ -203,4 +203,4 @@ local_settings_file = os.environ.get(
 )
 if os.path.exists(local_settings_file):
     with open(local_settings_file) as fd:
-        exec(fd.read())
+        exec(fd.read())  # noqa pylint: disable=exec-used