Move uses of to_bytes, to_text, to_native to use the module_utils version (#17423)

We couldn't copy to_unicode, to_bytes, to_str into module_utils because
of licensing.  So once created it we had two sets of functions that did
the same things but had different implementations.  To remedy that, this
change removes the ansible.utils.unicode versions of those functions.

lib/ansible/plugins/callback/tree.py

@@ -20,10 +20,10 @@ __metaclass__ = type
 
 import os
 
+from ansible.constants import TREE_DIR
+from ansible.module_utils._text import to_bytes
 from ansible.plugins.callback import CallbackBase
 from ansible.utils.path import makedirs_safe
-from ansible.utils.unicode import to_bytes
-from ansible.constants import TREE_DIR
 
 
 class CallbackModule(CallbackBase):
@@ -68,4 +68,3 @@ class CallbackModule(CallbackBase):
 
     def v2_runner_on_unreachable(self, result):
         self.result_to_tree(result)
-