Add expense number at Expenses (#406)

* add expense number at expenses

* Re-order expense fields

* Rename expense_number migration

* Add expense_number to tests

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Co-authored-by: Darko Gjorgjijoski <dg@darkog.com>

app/Http/Requests/ExpenseRequest.php

@@ -26,6 +26,11 @@ class ExpenseRequest extends FormRequest
             'expense_date' => [
                 'required',
             ],
+            'expense_number' => [
+                'nullable',
+                'string',
+                'max:255',
+            ],
             'expense_category_id' => [
                 'required',
             ],