chore: update WebUI to 2.8.0

[sinkuu]

It seems to have been overlooked.
https://github.com/ipfs-shipyard/ipfs-webui/releases/v2.8.0

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[lidel]

Thank you @sinkuu, we indeed skipped this one 😬
We hoped to have another release right after it, but other things took priority, so it makes sense to use v2.8.0 for now.

@Stebalien fysa v2.8.0 summary: it fixes drag&drop issues with directories and has improved Peers map

I tested and looks ok, plus we've been using it in ipfs-desktop for a while, so should be safe to merge.

[Stebalien]

Merged into master so you have until the next release (0.7.0) to fix anything.