Why leapp fails with "GLib.GError: g-key-file-error-quark: Key file does not start with a group (4)" error?

Issue

• Leapp fails with the following error:

  Risk Factor: high (error)
  Title: Actor network_manager_connection_scanner unexpectedly terminated with exit code: 1
  Summary: Traceback (most recent call last):
  File "/usr/lib/python3.6/site-packages/leapp/repository/actor_definition.py", line 74, in _do_run
  actor_instance.run(*args, **kwargs)
  File "/usr/lib/python3.6/site-packages/leapp/actors/__init__.py", line 289, in run
  self.process(*args)
  File "/etc/leapp/repos.d/system_upgrade/el8toel9/actors/networkmanagerconnectionscanner/actor.py", line 18, in process
  networkmanagerconnectionscanner.process()
  File "/etc/leapp/repos.d/system_upgrade/el8toel9/actors/networkmanagerconnectionscanner/libraries/networkmanagerconnectionscanner.py", line 60, in process
  process_dir(NM_CONN_DIR)
  File "/etc/leapp/repos.d/system_upgrade/el8toel9/actors/networkmanagerconnectionscanner/libraries/networkmanagerconnectionscanner.py", line 55, in process_dir
  process_file(os.path.join(NM_CONN_DIR, f))
  File "/etc/leapp/repos.d/system_upgrade/el8toel9/actors/networkmanagerconnectionscanner/libraries/networkmanagerconnectionscanner.py", line 29, in process_file
  keyfile.load_from_file(filename, GLib.KeyFileFlags.NONE)
  GLib.GError: g-key-file-error-quark: Key file does not start with a group (4)