IBX-301: Fixed manual cache clearing

[mateuszbieniek]

Question	Answer
JIRA issue	IBX-301
Type	bug
Target Ibexa version	v4.1
BC breaks	no

Looks like the fix for bad cache cleared got lost on the way (#22 - not sure how).

Description from the previous PR:

When the cache:clear command is executed it is making a check if cache "is fresh":
https://github.com/symfony/symfony/blob/5.4/src/Symfony/Bundle/FrameworkBundle/Command/CacheClearCommand.php#L132

When we execute rm -rf var/cache/prod/. beforehand cache:clear script is "tricked" into thinking that cache is fresh, as the request timestamp will be lower than Container File modification timestamp.

bulbo@bulboPC:/www/experience-3.3$ rm -rf var/cache/prod/.
bulbo@bulboPC:/www/experience-3.3$ php bin/console c:c --env=prod

// Clearing the cache for the prod environment with debug
// false

$_SERVER['REQUEST_TIME']: ^ 1635942532
filemtime($containerFile): ^ 1635942536
time(): ^ 1635942536

This is due to that deleted files are firstly recreated (which will also affect filemtime($containerFile)) when cache:clear is called, and then Command logic executes.

To fix this, a whole var/cache/prod directory content should be removed.

[mateuszbieniek]

Tests failing are not related to these PR changes.