Docs: Clean up of 'blockinfile' module docs (#46331)

* Docs: Clean up of 'blockinfile' module docs

This is part of a series of module doc cleanups.

* A few more fixes after review

lib/ansible/utils/module_docs_fragments/validate.py

@@ -1,29 +1,16 @@
-# Copyright (c) 2015 Ansible, Inc
-#
-# This file is part of Ansible
-#
-# Ansible is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# Ansible is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
+# -*- coding: utf-8 -*-
+
+# Copyright: (c) 2015, Ansible, Inc
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
 
 
 class ModuleDocFragment(object):
-
     # Standard documentation fragment
-    DOCUMENTATION = '''
+    DOCUMENTATION = r'''
 options:
-    validate:
-      description:
-       - The validation command to run before copying into place. The path to the file to
-         validate is passed in via '%s' which must be present as in the example below.
-         The command is passed securely so shell features like expansion and pipes won't work.
+  validate:
+    description:
+    - The validation command to run before copying into place.
+    - The path to the file to validate is passed in via '%s' which must be present as in the examples below.
+    - The command is passed securely so shell features like expansion and pipes will not work.
 '''