Fix streaming with python3+ (#103)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: apatard

tests/test_vagrant.py

@@ -596,7 +596,7 @@ def test_streaming_output(vm_dir):
     """
     Test streaming output of up or reload.
     """
-    test_string = "Waiting for machine to boot."
+    test_string = "Machine already provisioned"
     v = vagrant.Vagrant(vm_dir)
 
     with pytest.raises(subprocess.CalledProcessError):

vagrant/__init__.py

@@ -1039,7 +1039,6 @@ def _stream_vagrant_command(self, args):
                 env=self.env,
                 stdout=subprocess.PIPE,
                 stderr=err_fh,
-                bufsize=1,
             )
 
             # Iterate over output lines.