feature #35890 [Cache] give control over cache prefix seed (Tobion)

This PR was merged into the 5.2-dev branch.

Discussion
----------

[Cache] give control over cache prefix seed

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       |
| License       | MIT
| Doc PR        |

Reopened #35723 for master.

The configurable cache prefix seed does not give full control over the cache prefix because the container class is added to the prefix in any case. This is a problem because the container class contains the app env name. We use different app environments for different deployment targets (dev and test). We want dev and test to use the same redis cache. But this is impossible to achieve because even setting the cache prefix seed does not accomplish this.

Commits
-------

6681b92524 [Cache] give control over cache prefix seed

Author: fabpot

Tests/DependencyInjection/SecurityExtensionTest.php

@@ -366,6 +366,7 @@ public function testRememberMeCookieInheritFrameworkSessionCookie($config, $same
         $container->setParameter('kernel.bundles_metadata', []);
         $container->setParameter('kernel.project_dir', __DIR__);
         $container->setParameter('kernel.cache_dir', __DIR__);
+        $container->setParameter('kernel.container_class', 'app');
 
         $container->loadFromExtension('security', [
             'firewalls' => [