Error Reporting can report stack traces collected from Rust applications

## Announcement Announcement Error Reporting can report stack traces collected from Rust applications using [std::backtrace](https://doc.rust-lang.org/std/backtrace/index.html). To enable, set the `RUST_BACKTRACE=1` environment variable and make sure debug symbols are enabled. For more information, see[ReportedErrorEvent](https://cloud.google.com/error-reporting/reference/rest/v1beta1/projects.events/report.html?rep%5Flocation=global#reportederrorevent).