chore: Update upstream OpenTelemetry agent version and related depend…

…... (#435)

... encies

Made with ❤️️ by updatecli

Co-authored-by: elastic-observability-automation[bot] <180520183+elastic-observability-automation[bot]@users.noreply.github.com>

gradle/libs.versions.toml

@@ -10,11 +10,11 @@ opentelemetryProto = "1.3.2-alpha"
 
 # otel agent, we rely on the '*-alpha' and get the non-alpha dependencies transitively
 # updated from upstream agent with .ci/update-upstream.sh
-opentelemetryJavaagentAlpha = "2.8.0-alpha"
+opentelemetryJavaagentAlpha = "2.9.0-alpha"
 
 # otel contrib
 # updated from upstream agent with .ci/update-upstream.sh
-opentelemetryContribAlpha = "1.38.0-alpha"
+opentelemetryContribAlpha = "1.39.0-alpha"
 
 # otel semconv
 # updated from upstream agent with .ci/update-upstream.sh