Bump opentelemetry from 0.19.0 to 0.21.0

Bumps [opentelemetry](https://github.com/open-telemetry/opentelemetry-rust) from 0.19.0 to 0.21.0.
- [Release notes](https://github.com/open-telemetry/opentelemetry-rust/releases)
- [Commits](open-telemetry/opentelemetry-rust@v0.19.0...v0.21.0)

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

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

crates/telemetry/Cargo.toml

@@ -16,7 +16,7 @@ description  = """
 ibc-relayer-types = { version = "0.26.4", path = "../relayer-types" }
 
 once_cell                = "1.19.0"
-opentelemetry            = { version = "0.19.0", features = ["metrics"] }
+opentelemetry            = { version = "0.21.0", features = ["metrics"] }
 opentelemetry-prometheus = "0.12.0"
 prometheus               = "0.13.2"
 moka                     = { version = "0.12.0", features = ["sync"] }