Switch integer values to int32

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include/caosdb/transaction.h

@@ -365,6 +365,10 @@ public:
   [[nodiscard]] inline auto GetStatus() const noexcept -> TransactionStatus { return this->status; }
 
   [[nodiscard]] inline auto GetResultSet() const noexcept -> const ResultSet & {
+    if (!this->result_set) {
+      this->result_set = std::make_unique<MultiResultSet>(
+          std::move(std::vector<std::unique_ptr<Entity>>()));
+    }
     return *(this->result_set.get());
   }