Improve idempotency for volumes with slashes

In case of trailing slash or double slashes, the Podman strips it
automatically. Prepare input data accordingly, so we can compare
with Podman inspected one.

plugins/modules/podman_container.py

@@ -1744,6 +1744,10 @@ class PodmanContainerDiff:
         return self._diff_update_and_compare('uts', before, after)
 
     def diffparam_volume(self):
+        def clean_volume(x):
+            '''Remove trailing and double slashes from volumes.'''
+            return x.replace("//", "/").rstrip("/")
+
         before = self.info['mounts']
         before_local_vols = []
         if before:
@@ -1757,7 +1761,9 @@ class PodmanContainerDiff:
             before = [":".join(v) for v in volumes]
             before_local_vols = [":".join(v) for v in local_vols]
         if self.params['volume'] is not None:
-            after = [":".join(v.split(":")[:2]) for v in self.params['volume']]
+            after = [":".join(
+                [clean_volume(i) for i in v.split(":")[:2]]
+            ) for v in self.params['volume']]
         else:
             after = []
         if before_local_vols:

tests/integration/targets/podman_container_idempotency/tasks/idem_volumes.yml

@@ -60,7 +60,7 @@
     name: idempotency
     state: present
     volumes:
-      - /opt:/somedir
+      - /opt/://somedir
     command: 1h
   register: test5
 
@@ -142,8 +142,8 @@
     state: present
     command: 1h
     volumes:
-      - "/opt:/anotherdir"
-      - "local_volume1:/data"
+      - "/opt//:/anotherdir"
+      - "local_volume1:/data/"
   register: test11
 
 - name: check test11