TL;DR **You can't and you shouldn't care**.

This can be a bit off-topic, but IPFS is not an immutable ledger, not at all. When you _publish_ via Remix, it at first tries with a local IPFS node, if it's not found it tries with Infura public node (`https://ipfs.infura.io:5001/api/v0/add?pin=true`) and it asks _to pin_ (to keep in cache) the content for some time.

It's up to the IPFS node to decide how long to keep the information available to other peers, usually, it gets deleted from cache (_unpinned_) if no peers request it after some time.