Upgrade Status module reports Varnish Purger using D9 deprecated functions

Problem/Motivation

I'm planning an upgrade to Drupal 9 and this module is flagged by the Upgrade Status module.

Steps to reproduce

Install current version of Varnish Purger and Upgrade Status module. Run upgrade status check.

Proposed resolution

Address reported issues:

Varnish Purger,  8.x-2.0
Scanned on Wed, 10/02/2021 - 05:15

FILE:
modules/contrib/varnish_purge/modules/varnish_purge_tags/src/Tests/CacheTagsTest
.php

STATUS         LINE                           MESSAGE                           
--------------------------------------------------------------------------------
Check manually      Class Drupal\purge\Tests\KernelTestBase not found.          
--------------------------------------------------------------------------------
Check manually 13   Class Drupal\purge\Tests\KernelTestBase not found.          
--------------------------------------------------------------------------------

FILE: modules/contrib/varnish_purge/src/Tests/VarnishBundledPurgerFormTest.php

STATUS         LINE                           MESSAGE                           
--------------------------------------------------------------------------------
Check manually      Class Drupal\purge_ui\Tests\PurgerConfigFormTestBase not    
                    found.                                                      
--------------------------------------------------------------------------------
Check manually 10   Class Drupal\purge_ui\Tests\PurgerConfigFormTestBase not    
                    found.                                                      
--------------------------------------------------------------------------------

FILE: modules/contrib/varnish_purge/src/Tests/VarnishPurgerFormTest.php

STATUS         LINE                           MESSAGE                           
--------------------------------------------------------------------------------
Check manually      Class Drupal\purge_ui\Tests\PurgerConfigFormTestBase not    
                    found.                                                      
--------------------------------------------------------------------------------
Check manually 10   Class Drupal\purge_ui\Tests\PurgerConfigFormTestBase not    
                    found.                                                      
--------------------------------------------------------------------------------

FILE: modules/contrib/varnish_purge/src/Tests/VarnishPurgerFormTestBase.php

STATUS         LINE                           MESSAGE                           
--------------------------------------------------------------------------------
Check manually      Class Drupal\purge_ui\Tests\PurgerConfigFormTestBase not    
                    found.                                                      
--------------------------------------------------------------------------------
Check manually 10   Class Drupal\purge_ui\Tests\PurgerConfigFormTestBase not    
                    found.                                                      
--------------------------------------------------------------------------------

FILE:
modules/contrib/varnish_purge/tests/src/Behat/features/bootstrap/VarnishPurgeFea
tureContext.php

STATUS         LINE                           MESSAGE                           
--------------------------------------------------------------------------------
Check manually 13   Class VarnishPurgeFeatureContext implements deprecated      
                    interface Behat\Behat\Context\SnippetAcceptingContext: will 
                    be removed in 4.0. Use --snippets-for CLI option instead    
--------------------------------------------------------------------------------
Fix now        70   Call to deprecated function node_load_multiple(). Deprecated
                    in drupal:8.0.0 and is removed from drupal:9.0.0. Use       
                    \Drupal\node\Entity\Node::loadMultiple().                   
--------------------------------------------------------------------------------

FILE: modules/contrib/varnish_purge

STATUS         LINE                           MESSAGE                           
--------------------------------------------------------------------------------
Check manually 0    The 'varnish_purger' extension is not installed. Cannot     
                    check deprecated library use.                               
--------------------------------------------------------------------------------