drop python3.6 support

python 3.6 reached end of life on 2021-12-23

Committed via https://github.com/asottile/all-repos
diff --git a/tests/fix_byte_order_marker_test.py b/tests/fix_byte_order_marker_test.py
index da150e3..d7a6599 100644
--- a/tests/fix_byte_order_marker_test.py
+++ b/tests/fix_byte_order_marker_test.py
@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from pre_commit_hooks import fix_byte_order_marker