Enable "fix-byte-order-marker" pre-commit hook and apply fixes

Author: ulgens

.pre-commit-config.yaml

@@ -23,6 +23,7 @@ repos:
           - id: file-contents-sorter
             files: ^(requirements/\w*.txt)$
             args: ["--ignore-case", "--unique"]
+          - id: fix-byte-order-marker
           - id: mixed-line-ending
 
     - repo: https://github.com/asottile/pyupgrade