##### SUMMARY
`callback_whitelist = profile_tasks` in ansible.cfg does not activate `ansible.posix.profile_tasks`.

This breaks 2.9 compatibility.

CC @nitzmahone (as discussed on IRC)

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
collection redirection

##### ANSIBLE VERSION
devel
self._workers = []
        for i in range(num):
            self._workers.append(None)
    def load_callbacks(self):
        '''
        Loads all available callbacks, with the exception of those which
        utilize the CALLBACK_TYPE option. When CALLBACK_TYPE is set to 'stdout',
        only one such callback plugin will be loaded.
        '''
        if self._callbacks_loaded:
            return
        stdout_callback_loaded = False
        if self._stdout_callback is None:
            self._stdout_callback = C.DEFAULT_STDOUT_CALLBACK
        if isinstance(self._stdout_callback, CallbackBase):
            stdout_callback_loaded = True
        elif isinstance(self._stdout_callback, string_types):
            if self._stdout_callback not in callback_loader:
                raise AnsibleError("Invalid callback for stdout specified: %s" % self._stdout_callback)
            else:
                self._stdout_callback = callback_loader.get(self._stdout_callback)
                self._stdout_callback.set_options()
                stdout_callback_loaded = True
        else: