chore: support yamux to wherever mplex is supported (#1579)

Adds yamux to all tests, docs and examples.

Closes #1578

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Co-authored-by: achingbrain <alex@achingbrain.net>

.aegir.js

@@ -3,6 +3,7 @@ import { mplex } from '@libp2p/mplex'
 import { noise } from '@chainsafe/libp2p-noise'
 import { pipe } from 'it-pipe'
 import { createFromJSON } from '@libp2p/peer-id-factory'
+import { yamux } from '@chainsafe/libp2p-yamux'
 
 /** @type {import('aegir').PartialOptions} */
 export default {
@@ -36,6 +37,7 @@ export default {
           webSockets()
         ],
         streamMuxers: [
+          yamux(),
           mplex()
         ],
         connectionEncryption: [