ci: use macos and ubuntu runners with `cargo nextest`

[nxsaken]

Context

Integration tests have been broken for a while now, apparently due to slow self-hosted runners. This PR addresses that and some.

Solution

• Switch most jobs to macos-latest
• Switch pytests to ubuntu-latest
• Use cargo nextest instead of cargo test (closes #4987)

Additional

• Run unit tests with no-default-features (closes #4854)
• Retry client pytests (follow-up ticket: https://github.com/hyperledger/iroha/issues/5014)
• Do not build/download the default executor where it's not needed (post #4931)
• Caching dependencies should actually work now (switch from rust-cache to cargo-cache), cache is shared between similar jobs

---

Checklist

• [x] Finish fixing client pytests
• [x] I've read CONTRIBUTING.md.
• [ ] (optional) I've written unit tests for the code changes.
• [x] All review comments have been resolved.

[nxsaken]

Squashed commits to resolve conflicts faster, removed retries in extra_functional tests. Nothing else changed

[0x009922]

Looks good, what prevents from undrafting & merging it?

[nxsaken]

@0x009922 the self-hosted runners seem to be working fine again, and macOS runners stopped being faster. We agreed with @BAStos525 a while ago to wait and compare before deciding whether to ditch the macOS runners and merge the rest of the changes. I'll pick this up today

[nxsaken]

@BAStos525 UI tests fail with the disk space issue you've mentioned before, should they also use the self-hosted runners?

[BAStos525]

@BAStos525 UI tests fail with the disk space issue you've mentioned before, should they also use the self-hosted runners?

Sure. We can try self-hosted runners