Use correct backtick for regex escape

[drscream]

Overall Review of Changes:
Depends on the ansible version regex escape (via slash) require correct backticks to work. Otherwise it would result in a syntax error.

Issue Fixes:

ERROR! We were unable to read either as JSON nor YAML, these are the errors we got from each:
JSON: Expecting value: line 1 column 1 (char 0)
Syntax Error while loading YAML.
  found unknown escape character
The error appears to be in '/runner/project/tasks/section_4/cis_4.2.2.x.yml': line 188, column 25, but may
be elsewhere in the file depending on the exact syntax problem.
The offending line appears to be:
            path: "{{ systemd_conf_file | default('/usr/lib/tmpfiles.d/systemd.conf') }}"
            regexp: "^z \/var\/log\/journal\/%m\/system.journal (!?06(0|4)0) root"
                        ^ here

How has this been tested?:
The issue was detected with the latest Ansible Tower / Ansible Automation Platform version. After adding the change in the merge request the playbook worked.

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[uk-bolly]

good find thank you

[uk-bolly]

hi @drscream

Thank you for taking the time in raising this PR. The content looks good, we do however required both GPG signing and signed-off-by added to each commit in order to merge.
If you could added the required signing happy to merge this.

Many thanks

uk-bolly

[drscream]

Hello @uk-bolly

thanks for your reply, I've signed the commit :-)

All the best,
Thomas