chore(ci): use manual x-dist value for self-hosted runners

[spencer-tb]

🗒️ Description

To speed up the release process I've added a new user to the hive server called usainbolt. This user will be used entirely as a self-hosted runner set for the Build and Package Fixtures workflow step. Note this is only runs when creating new releases.

Currently our releases take a long time finish as fixture builds run sequentially, due to our single self-hosted runner instance. Everything in total currently takes around 5hrs. I've now added 6 self hosted runners.

This will take our entire release process time down to <3hrs. Note we could improve this by finding a way to fill the slow marked fixtures faster, ideally giving us a release build time of <30mins.

Other Changes

• Removed pectra-devnet-6 as a separate build, Prague tests are within develop now.
• Set x-dist to 10 instead of auto. With the self-hosted runners when using auto it will select n=32 for each build. This will ultimately throttle the EELS resolver and give us timeout errors when filing.

🔗 Related Issues

#1051

✅ Checklist

• All: Set appropriate labels for the changes.
• All: Considered squashing commits to improve commit history.
• All: Added an entry to CHANGELOG.md.
• All: Considered updating the online docs in the ./docs/ directory.

[danceratopz]

The changes LGTM, but I'm missing the multiple runners config. I guess this needs to be added to the repo settings?

[spencer-tb]

The changes LGTM, but I'm missing the multiple runners config. I guess this needs to be added to the repo settings?

It's all done on the server side! :D