Follow up: Fix CI failure introduced in 0b8b6148b
Follow up: Fix CI failure introduced in 0b8b6148b

The previous commit introduced a CI failure which was caused by a test depending on the execution time. The Twitter channel implementation ignores tweets older than 15 days.
Therefore we need to travel to the time when the VCR snapshot was recorded to fix it.

zammad/zammad,monotek/zammad,zammad/zammad,monotek/zammad,monotek/zammad,monotek/zammad,monotek/zammad,zammad/zammad,monotek/zammad,zammad/zammad,zammad/zammad,zammad/zammad