Deleting all rules only deletes some of them

[tredondo]

Describe the bug

• OpenSnitch version 1.6.7
• OS: Fedora
• Window Manager: KDE

To Reproduce

1. Go to 'Rules -> Temporary'
2. Click a rule
3. Press Ctrl+A
4. Press Del

Already an error here, the prompt says "You are about to delete this rule" (singular), when multiple rules are selected.

5. Press Yes to delete all rules.
6. Notice that many rules are left:

Screenshots

[e3dio]

There is a serious bug with deleting rules that I explained here #1245 He did not do a release with the fix yet, you need this PR #1252