Improve docstring state.result for when used with run_deployment

[benjamincerigo]

To give light on the complex behaviour of state.result when used with run_deployment.

Closes #15276

Checklist

• This pull request references any related issue by including "closes <link to issue>"
  • If no issue exists and your change is not a small fix, please create an issue first.
• If this pull request adds new functionality, it includes unit tests that cover the changes
• If this pull request removes docs files, it includes redirect settings in mint.json.
• If this pull request adds functions or classes, it includes helpful docstrings.

[codspeed-hq]

CodSpeed Performance Report

Merging #15509 will not alter performance

_{Comparing benjamincerigo:improve_docs_state_result_raise_on_failure (e832383) with main (953b733)}

Summary

✅ 3 untouched benchmarks

[desertaxle]

Thank you!