bundles/backup-client: metadata backup-pre-hooks now use /bin/sh by default

bundles/backup-client/items.py

@@ -36,6 +36,6 @@ directories['/etc/backup-pre-hooks.d'] = {
 
 for hname, hcontent in node.metadata['backup-client'].get('pre-hooks', {}).items():
     files[f'/etc/backup-pre-hooks.d/{hname}'] = {
-        'content': hcontent,
+        'content': '#!/bin/sh\n\n' + hcontent,
         'mode': '0700',
     }

nodes/htz/ex42-1048908.py

@@ -74,7 +74,6 @@ nodes['htz.ex42-1048908'] = {
         'backup-client': {
             'pre-hooks': {
                 'kunsi-weechat': \
-                    '#!/bin/sh\n' \
                     'echo \'core.weechat */layout store\' >> /home/kunsi/.weechat/weechat_fifo\n' \
                     'echo \'core.weechat */save\' >> /home/kunsi/.weechat/weechat_fifo\n',
             },