Remove _level_to_color call that doesn't exist

Fixes #10990

Author: ericholscher

readthedocs/core/logs.py

@@ -112,7 +112,6 @@ def __call__(self, logger, name, event_dict):
         if level is not None:
             sio.write(
                 "["
-                + self._level_to_color.get(level, "")
                 + _pad(level, self._longest_level)
                 + self._styles.reset
                 + "] "