Issue #2516842 by er.pushpinderrana, jhodgdon: Fix indentation in UPGRADE.txt

core/UPGRADE.txt

@@ -80,12 +80,12 @@ following the instructions in the INTRODUCTION section at the top of this file:
      database information, and you will also want to copy in any other
      customizations you have added.
 
-     You can find the release notes for your version at
-     https://www.drupal.org/project/drupal. At bottom of the project page under
-     "Downloads" use the link for your version of Drupal to view the release
-     notes. If your version is not listed, use the 'View all releases' link.
-     From this page you can scroll down or use the filter to find your version
-     and its release notes.
+   You can find the release notes for your version at
+   https://www.drupal.org/project/drupal. At bottom of the project page under
+   "Downloads" use the link for your version of Drupal to view the release
+   notes. If your version is not listed, use the 'View all releases' link. From
+   this page you can scroll down or use the filter to find your version and its
+   release notes.
 
 4. Download the latest Drupal 8.x release from https://www.drupal.org to a
    directory outside of your web root. Extract the archive and copy the files