Merge #6814: fix: Reset all collections before reading in CDeterministicMNListDiff::Unserialize()

8e0e63f fix: Reset all collections before reading in `CDeterministicMNListDiff::Unserialize()` (UdjinM6)

Pull request description:

  ## Issue being fixed or feature implemented
  Fix the issue found by @coderabbitai while reviewing #6813 #6813 (review)

  ## What was done?

  ## How Has This Been Tested?

  ## Breaking Changes
  n/a

  ## Checklist:
  - [ ] I have performed a self-review of my own code
  - [ ] I have commented my code, particularly in hard-to-understand areas
  - [ ] I have added or updated relevant unit/integration/functional/e2e tests
  - [ ] I have made corresponding changes to the documentation
  - [ ] I have assigned this pull request to a milestone _(for repository code-owners and collaborators only)_

ACKs for top commit:
  kwvg:
    utACK 8e0e63f

Tree-SHA512: 22fe37720a87052b450c33c0a51537058b776d103981506b3556e7be76c0a3390764d089bb16bac0722468754eadf77177fd8d39b873121a1f9fdbf7220710d0

Author: PastaPastaPasta

src/evo/deterministicmns.h

@@ -540,6 +540,8 @@ class CDeterministicMNListDiff
     template <typename Stream>
     void Unserialize(Stream& s)
     {
+        // Reset all collections before reading
+        addedMNs.clear();
         updatedMNs.clear();
         removedMns.clear();