Updated YABS table for GB5 values to be nullable

Updated YABS table for GB5 values to be nullable

database/migrations/2022_09_22_020501_update_yabs_table.php

@@ -0,0 +1,18 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up()
+    {
+        Schema::table('yabs', function($table)
+        {
+            $table->integer('gb5_single')->nullable()->change();
+            $table->integer('gb5_multi')->nullable()->change();
+            $table->integer('gb5_id')->nullable()->change();
+        });
+    }
+};