docker_image: Fix up 'changed' event in force mode (#33754)

* docker_image: Fix up 'changed' event in force mode

This is the same as https://github.com/ansible/ansible/pull/19235 except it applies to all image-building modes (building the image locally, loading the image from an archive, or pulling the image), rather than only when pulling the image.

* Use 'dummy' rather than '_' as unused variable name.

* Add changelog fragment for pull request #33754

changelogs/fragments/33754-docker_image_fix_changed_in_force_mode.yaml

@@ -0,0 +1,2 @@
+minor_changes:
+- "docker_image - set ``changed`` to ``false`` when using ``force: yes`` to load or build an image that ends up being identical to one already present on the Docker host."

lib/ansible/modules/cloud/docker/docker_image.py

@@ -348,9 +348,9 @@ class ImageManager(DockerBaseClass):
                 self.results['actions'].append('Pulled image %s:%s' % (self.name, self.tag))
                 self.results['changed'] = True
                 if not self.check_mode:
-                    self.results['image'], already_latest = self.client.pull_image(self.name, tag=self.tag)
-                    if already_latest:
-                        self.results['changed'] = False
+                    self.results['image'], dummy = self.client.pull_image(self.name, tag=self.tag)
+            if not self.check_mode and image and image['Id'] == self.results['image']['Id']:
+                self.results['changed'] = False
 
         if self.archive_path:
             self.archive_image(self.name, self.tag)