Bump yarn to 4.1.1 and remove Volta config

[rakyi]

I noticed we had two different versions of Yarn in deps, so I made it the same and also updated it to the latest given I was touching it anyway.

[marcelgerber]

Hi! We're currently still using a yarnPath-based Yarn installation.

Yarn nowadays recommends to use Corepack, which ships with recent versions of Node, but is disabled by default (can be enabled using corepack enable). We should probably switch over to Corepack at some point in the near future (and thereby tell the team to enable it), but for now let's stay with yarnPath.

For that to work correctly, you'll need to also run yarn set version latest in order to update the Yarn release that's then included with the repo. Thank you!

[rakyi]

Thanks, I ran the command to update Yarn properly.

[rakyi]

After thinking about this more, we don't really need Volta when we are using the yarnPath and we also have .nvmrc that tools like nvm and fnm use, so I decided to remove the Volta config. I'll keep the PR open for a bit in case someone from the team will object to the removal in Slack.

[marcelgerber]

Great thanks!