lxd_container: Create container via fingerprint (#52737)

In addition to using creating container using image
aliases, containers can also be created using
fingerprints, provided that the playbook author provide
alternate values for 'server', 'protocol' and swap out
'alias' for 'fingerprint'.

+label: docsite_pr

lib/ansible/modules/cloud/lxd/lxd_container.py

@@ -181,6 +181,30 @@ EXAMPLES = '''
       raw: apt-get install -y python
       when: python_install_check.rc == 1
 
+# An example for creating an Ubuntu 14.04 container using an image fingerprint.
+# This requires changing 'server' and 'protocol' key values, replacing the
+# 'alias' key with with 'fingerprint' and supplying an appropriate value that
+# matches the container image you wish to use.
+- hosts: localhost
+  connection: local
+  tasks:
+    - name: Create a started container
+      lxd_container:
+        name: mycontainer
+        state: started
+        source:
+          type: image
+          mode: pull
+          # Provides current (and older) Ubuntu images with listed fingerprints
+          server: https://cloud-images.ubuntu.com/releases
+          # Protocol used by 'ubuntu' remote (as shown by 'lxc remote list')
+          protocol: simplestreams
+          # This provides an Ubuntu 14.04 LTS amd64 image from 20150814.
+          fingerprint: e9a8bdfab6dc
+        profiles: ["default"]
+        wait_for_ipv4_addresses: true
+        timeout: 600
+
 # An example for deleting a container
 - hosts: localhost
   connection: local