Bump io.opentelemetry.semconv:opentelemetry-semconv

Bumps [io.opentelemetry.semconv:opentelemetry-semconv](https://github.com/open-telemetry/semantic-conventions-java) from 1.25.0-alpha to 1.28.0-alpha.
- [Release notes](https://github.com/open-telemetry/semantic-conventions-java/releases)
- [Changelog](https://github.com/open-telemetry/semantic-conventions-java/blob/main/CHANGELOG.md)
- [Commits](https://github.com/open-telemetry/semantic-conventions-java/commits)

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

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

riptide-opentelemetry/pom.xml

@@ -18,7 +18,7 @@
 
     <properties>
         <opentelemetry.version>1.39.0</opentelemetry.version>
-        <opentelemetry-semconv.version>1.25.0-alpha</opentelemetry-semconv.version>
+        <opentelemetry-semconv.version>1.28.0-alpha</opentelemetry-semconv.version>
     </properties>
 
     <dependencyManagement>