validate-modules: Fix all system modules (#52384)

This PR includes validate-modules fixes for all system modules.
Except a few that are deliberately implemented like this.

lib/ansible/modules/system/cronvar.py

@@ -20,58 +20,65 @@ ANSIBLE_METADATA = {'metadata_version': '1.1',
                     'status': ['preview'],
                     'supported_by': 'community'}
 
-DOCUMENTATION = """
+DOCUMENTATION = r'''
 ---
 module: cronvar
 short_description: Manage variables in crontabs
 description:
-  - Use this module to manage crontab variables. This module allows
-    you to create, update, or delete cron variable definitions.
+  - Use this module to manage crontab variables.
+  - This module allows you to create, update, or delete cron variable definitions.
 version_added: "2.0"
 options:
   name:
     description:
       - Name of the crontab variable.
+    type: str
     required: yes
   value:
     description:
       - The value to set this variable to.
       - Required if C(state=present).
+    type: str
   insertafter:
     description:
       - If specified, the variable will be inserted after the variable specified.
       - Used with C(state=present).
+    type: str
   insertbefore:
     description:
       - Used with C(state=present). If specified, the variable will be inserted
         just before the variable specified.
+    type: str
   state:
     description:
       - Whether to ensure that the variable is present or absent.
+    type: str
     choices: [ absent, present ]
     default: present
   user:
     description:
       - The specific user whose crontab should be modified.
-    default: root
+      - This parameter defaults to C(root) when unset.
+    type: str
   cron_file:
     description:
       - If specified, uses this file instead of an individual user's crontab.
-        Without a leading /, this is assumed to be in /etc/cron.d.  With a leading
-        /, this is taken as absolute.
+      - Without a leading C(/), this is assumed to be in I(/etc/cron.d).
+      - With a leading C(/), this is taken as absolute.
+    type: str
   backup:
     description:
       - If set, create a backup of the crontab before it is modified.
         The location of the backup is returned in the C(backup) variable by this module.
     type: bool
-    default: 'no'
+    default: no
 requirements:
   - cron
 author:
 - Doug Luce (@dougluce)
-"""
+'''
 
-EXAMPLES = '''
+EXAMPLES = r'''
 - name: Ensure entry like "EMAIL=doug@ansibmod.con.com" exists
   cronvar:
     name: EMAIL