Bump dotenv from 0.13.0 to 0.15.0 in /rust_thruster_st_bench

Bumps [dotenv](https://github.com/dotenv-rs/dotenv) from 0.13.0 to 0.15.0.
- [Release notes](https://github.com/dotenv-rs/dotenv/releases)
- [Changelog](https://github.com/dotenv-rs/dotenv/blob/master/CHANGELOG.md)
- [Commits](dotenv-rs/dotenv@v0.13.0...v0.15.0)

---
updated-dependencies:
- dependency-name: dotenv
  dependency-version: 0.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

rust_thruster_st_bench/Cargo.lock

@@ -12,7 +12,7 @@ lto = true
 [dependencies]
 async-trait = "0.1"
 bytes = "1.2.1"
-dotenv = "0.13.0"
+dotenv = "0.15.0"
 env_logger = "0.7.1"
 log = "0.4"
 hyper = "0.14.19"