Added unless force statement to not_if of execute block.

[donwlewis]

Description

This change allows the force option to behave as expected.

Issues Resolved

42

Check List

I am new to the testing bit, but I will try and get these tests done. I have tested on RHEL 7.4 system in my environment, and it behaves has expected.

• [ ] All tests pass. See https://github.com/chef-cookbooks/community_cookbook_documentation/blob/master/TESTING.MD
• [ ] New functionality includes testing.
• [ ] New functionality has been documented in the README if applicable
• [ ] All commits have been signed for the Developer Certificate of Origin. See https://github.com/chef-cookbooks/community_cookbook_documentation/blob/master/CONTRIBUTING.MD