Check the size of video captures artifacts after a while

Originally created by @bertagaz on #10354 (Redmine)

We’ve setup our build system to archive the video artifacts as tracked in tails/sysadmin#10154. But we should check after a reasonable amount of time (let say a release cycle) how much disk space that really means, and if we need to keep less of them.

Blueprint: https://tails.boum.org/blueprint/automated_builds_and_tests/automated_tests_specs/

Parent Task: tails/sysadmin#10153

Related issues

• Related to tails/tails#10155