gx: update go-cid

[kevina]

Depends on:

• gx: update go-cid libp2p/go-libp2p-kad-dht#186
• gx: update go-cid go-ipld-git#22
• gx: update go-cid go-ipfs-chunker#2
• gx: update go-cid go-ipfs-exchange-offline#4
• gx: update go-cid libp2p/go-libp2p-routing-helpers#4
• gx: update go-cid libp2p/go-libp2p-pubsub-router#5
• gx: update go-cid go-path#4

This PR with gx updates has been created using gx-workspace: https://github.com/ipfs/gx-workspace

[schomatis]

For the record, it was the go-ipfs-chunker dependency updated here which had the old version of go-cid that was causing the failed rewrite in gx-go link when trying to test #7. I should check out the gx-workspace tool.