postgresql_db: fix restoring from SQL files would execute the file twice (ansible-collections#883)

Author: Andersson007

changelogs/fragments/882-postgresql_db-restore-fix.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - postgresql_db - restoring from ``.sql`` files would execute the file twice. The module now avoids using both ``--file`` and stdin redirection simultaneously (https://github.com/ansible-collections/community.postgresql/issues/882). 

plugins/modules/postgresql_db.py

@@ -646,7 +646,7 @@ def db_restore(module, target, target_opts="",
     else:
         if any(substring in cmd for substring in ['--format=Directory', '--format=Custom']):
             cmd = '{0} {1}'.format(cmd, shlex_quote(target))
-        else:
+        elif '--file=' not in cmd:
             cmd = '{0} < {1}'.format(cmd, shlex_quote(target))
 
     return do_with_password(module, cmd, password)