Clean up module documentation (#36909)

* Clean up module documentation

This PR includes:
- Removal of `default: None` (and variations)
- Removal of `required: false`
- Fixing booleans and `type: bool` where required

* Fix remaining (new) validation issues

lib/ansible/modules/cloud/openstack/os_network.py

@@ -30,35 +30,30 @@ options:
    shared:
      description:
         - Whether this network is shared or not.
-     required: false
-     default: false
+     type: bool
+     default: 'no'
    admin_state_up:
      description:
         - Whether the state should be marked as up or down.
-     required: false
-     default: true
+     type: bool
+     default: 'yes'
    external:
      description:
         - Whether this network is externally accessible.
-     required: false
-     default: false
+     type: bool
+     default: 'no'
    state:
      description:
         - Indicate desired state of the resource.
      choices: ['present', 'absent']
-     required: false
      default: present
    provider_physical_network:
      description:
         - The physical network where this network object is implemented.
-     required: false
-     default: None
      version_added: "2.1"
    provider_network_type:
      description:
         - The type of physical network that maps to this network resource.
-     required: false
-     default: None
      version_added: "2.1"
    provider_segmentation_id:
      description:
@@ -66,19 +61,14 @@ options:
           attribute defines the segmentation model. For example, if the
           I(network_type) value is vlan, this ID is a vlan identifier. If
           the I(network_type) value is gre, this ID is a gre key.
-     required: false
-     default: None
      version_added: "2.1"
    project:
      description:
         - Project name or ID containing the network (name admin-only)
-     required: false
-     default: None
      version_added: "2.1"
    availability_zone:
      description:
        - Ignored. Present for backwards compatibility
-     required: false
 requirements: ["shade"]
 '''