fix: GenAI client - Resolve opentelemetry dependency

PiperOrigin-RevId: 953363022

Author: sararob

setup.py

@@ -155,6 +155,7 @@
     "opentelemetry-exporter-gcp-trace < 2",
     "opentelemetry-exporter-otlp-proto-http < 2",
     "opentelemetry-instrumentation-google-genai>=0.3b0, <1.0.0",
+    "opentelemetry-resourcedetector-gcp>=1.5.0.dev0",
     "pydantic >= 2.11.1, < 3",
     "typing_extensions",
     "aiohttp",  # for ADK users to use aiohttp rather than httpx client