gh-runner: add rust-src as a component

[rphmeier]

Wasm build in 1.6.0 seems to require this. The runner needs to be re-deployed once it's merged.

[rphmeier]

Current dependencies on/for this PR:

• main
  • PR #206 👈

This stack of pull requests is managed by Graphite.

[pepyakin]

https://github.com/thrumdev/blobs/actions/runs/7646894989/job/20906951032 testing it here