chore(deps): update opentelemetry-semantic-conventions requirement

Updates the requirements on [opentelemetry-semantic-conventions](https://github.com/open-telemetry/opentelemetry-rust) to permit the latest version.
- [Release notes](https://github.com/open-telemetry/opentelemetry-rust/releases)
- [Commits](open-telemetry/opentelemetry-rust@v0.12.0...v0.12.0)

---
updated-dependencies:
- dependency-name: opentelemetry-semantic-conventions
  dependency-type: direct:production
...

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

Cargo.toml

@@ -61,7 +61,7 @@ native-tls = "0.2"
 once_cell = "1"
 openssl = "0.10"
 opentelemetry-http = { version = "0.9", default-features = false }
-opentelemetry-semantic-conventions = { version = "0.12", default-features = false }
+opentelemetry-semantic-conventions = { version = "0.13", default-features = false }
 opentelemetry-prometheus = { version = "0.13", default-features = false }
 opentelemetry = { version = "0.20", default-features = false }
 parking_lot = "0.12"