Fix binary mode open() call in _get_file_digest()

Remove incorrect encoding parameter from binary mode open() call.
Binary mode ('rb') doesn't accept encoding parameter.

This was incorrectly added in PR #24 (CJK encoding fix) which added
encoding to all open() calls, but binary mode doesn't accept encoding.

Fixes: ValueError: binary mode doesn't take an encoding argument
when running lock --update on projects with local file paths.

Author: Qonfused

ocebuild/sources/binary.py

@@ -40,7 +40,7 @@ def _get_stream_hash(stream, hash) -> str:
 
 def _get_file_digest(filename, hash) -> str:
   """Gets a digest for a file."""
-  with open(filename, 'rb', encoding="UTF-8") as file:
+  with open(filename, 'rb') as file:
     hash = _get_stream_hash(file, hash)
   return hash