Bump version number to v0.23.7 (#73)

Author: efb4f5ff-1298-471a-8973-3d47447115dc

src/index.php

@@ -1,11 +1,11 @@
 <?php
 require 'includes/header.php';
 
-$currentRelease = 'Release 0.23.6 Beta';
+$currentRelease = 'Release 0.23.7 Beta';
 
-$fullTagName = 'v0.23.6-beta';
+$fullTagName = 'v0.23.7-beta';
 
-$versionNumber = '0.23.6';
+$versionNumber = '0.23.7';
 
 $baseUrl = "https://github.com/FreeTubeApp/FreeTube/releases/download/";