Update list of peertube instances and test domain

[anoadragon453]

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• Bug fix
• Improvement
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• New feature

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Description of your pull request and other information

Update the list of PeerTube instances from https://instances.joinpeertube.org/instances. The list was quite stale and a lot more PeerTube instances are now available.

The test domain was updated from peertube.moe to peertube.cpy.re as peertube.cpy.re is the instance run by the group who make PeerTube. peertube.moe has since disappeared and thus the new list did not include them, causing the tests to fail.

[riking]

consider switching to autodetection instead of constantly updating a giant list that will always be out of date?

[dstftw]

Consider checking before posting?

[anoadragon453]

Relevant: #16733