Remove Composer dependency on config_actions

Problem/Motivation

The composer.json file for panopoly_core requires config_actions, which is going to be deprecated in favor of the Recipes initiative in D11. This module doesn't seem to be used in Panopoly - there are no config/actions directories and no dependencies listed in *.info.yml.

Steps to reproduce

N/A

Proposed resolution

Remove the dependency.

Remaining tasks

Patch and test.

User interface changes

N/A

API changes

N/A

Data model changes

N/A