chore: remove peer deps

[achingbrain]

We added ipfs-http-client as a peer dep to signal to the user
that they should add the modules they depend on as deps of their project.

Starting with npm7 all peer deps get installed automatically which
defeats the purpose of our use of peer deps, so let's remove them.

[vasco-santos]

Yes, we need to do this, but across all libp2p stack. Can you see and weight in on:

• [testing] fix node 15/16 install due to npm 7 changes js-libp2p#790
• Libp2p testing overhaul js-libp2p#857

We still have other modules and we need a solution for this. Let me know your thoughts in the 857 and I can use next week to get this done in libp2p

[achingbrain]

From my perspective this is more about installing the deps in the js-ipfs monorepo - ipfs-cli depends on the delegated-* modules, which then cause ipfs-http-client to be installed in /node_modules when it should be symlinked to /packages/ipfs-http-client, causing havok in the dep tree.

I think this PR and the sibling one libp2p/js-libp2p-delegated-peer-routing#44 can be treated as a separately thing to the libp2p testing effort in those linked issues!

[vasco-santos]

I will merge this PR for the time being. However, this will not solve the problem of npm7 for libp2p until we work on the mentioned issue