fix(docs): add 'become: true' to example playbooks. fix #787 (#804)

Signed-off-by: Sebastian Gumprich <[email protected]>

roles/os_hardening/README.md

@@ -145,7 +145,6 @@ This role is mostly based on guides by:
 <!-- BEGIN_ANSIBLE_DOCS -->
 
 ## Supported Operating Systems
-
 - EL
   - 8, 9
 - Ubuntu
@@ -999,6 +998,7 @@ None.
 
 ```
 - hosts: all
+  become: true
   roles:
     - name: devsec.hardening.os_hardening
 ```