Simplify edit transaction routine.

app/Repositories/Journal/JournalRepository.php

@@ -76,6 +76,16 @@ class JournalRepository implements JournalRepositoryInterface
         return new MessageBag;
     }
 
+    /**
+     * @param TransactionJournal $journal
+     *
+     * @return int
+     */
+    public function countTransactions(TransactionJournal $journal): int
+    {
+        return $journal->transactions()->count();
+    }
+
     /**
      * @param TransactionJournal $journal
      *