Update tracing-log requirement from 0.1 to 0.2

Updates the requirements on [tracing-log](https://github.com/tokio-rs/tracing) to permit the latest version.
- [Release notes](https://github.com/tokio-rs/tracing/releases)
- [Commits](tokio-rs/tracing@tracing-log-0.1.0...tracing-log-0.2.0)

---
updated-dependencies:
- dependency-name: tracing-log
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

examples/Cargo.toml

@@ -13,5 +13,5 @@ tracing = "0.1"
 tracing-logstash = { path = "../tracing-logstash" }
 tracing-subscriber = { version = "0.3", default-features = false, features = ["env-filter"] }
 
-tracing-log = { version = "0.1", features = ["log-tracer"] }
+tracing-log = { version = "0.2", features = ["log-tracer"] }
 log = "0.4"