[`BLIP`] update blip path on slow tests
# What does this PR do?

This PR updates the path to the image we use for running BLIP slow tests - as pointed out by @NielsRogge better to upload these images on the Hub in case they get removed from the original place
Happy also to move the Hub repo on `hf-internal-testing` but I am not a member of the org

Also the image is quite large, so I prefer to upload it on the Hub rather than pushing it on the repo here

cc @NielsRogge @sgugger 
_The documentation is not available anymore as the PR was closed or merged._<|||||>Can you add it to hf-internal-testing instead? Might be better there. Happy to merge any PR or approve your demand to join ;-)<|||||>Thanks for adding! I've transferred it :) <|||||>@sgugger , I think that we can merge this! 🙏 