Update env_logger requirement from 0.7.0 to 0.8.1

Updates the requirements on [env_logger](https://github.com/env-logger-rs/env_logger) to permit the latest version.
- [Release notes](https://github.com/env-logger-rs/env_logger/releases)
- [Changelog](https://github.com/env-logger-rs/env_logger/blob/master/CHANGELOG.md)
- [Commits](rust-cli/env_logger@v0.7.0...v0.8.1)

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

Cargo.toml

@@ -27,7 +27,7 @@ crossbeam-utils = "0.8"
 crypto-hash = "0.3.1"
 curl = { version = "0.4.23", features = ["http2"] }
 curl-sys = "0.4.22"
-env_logger = "0.7.0"
+env_logger = "0.8.1"
 pretty_env_logger = { version = "0.4", optional = true }
 anyhow = "1.0"
 filetime = "0.2.9"