Add prometheus metric tests based on a fictional electricity bidding market

tests/llm/fixtures/shared/python-flask-otel/Dockerfile

@@ -2,6 +2,7 @@ FROM python:3.11-slim
 
 # Install Flask and OpenTelemetry packages (for Tempo-based tests)
 # Plus additional packages needed for New Relic-based tests
+# Plus prometheus_client for Prometheus-based tests
 RUN pip install --no-cache-dir \
     flask==3.1.2 \
     opentelemetry-api==1.37.0 \
@@ -12,7 +13,8 @@ RUN pip install --no-cache-dir \
     opentelemetry-exporter-otlp-proto-grpc==1.37.0 \
     opentelemetry-proto==1.37.0 \
     opentelemetry-semantic-conventions==0.58b0 \
-    requests==2.32.3
+    requests==2.32.3 \
+    prometheus-client==0.21.1
 
 # Create app directory
 RUN mkdir /app

tests/llm/fixtures/shared/python-flask-otel/build.sh

@@ -6,7 +6,7 @@ set -e
 
 REGISTRY="me-west1-docker.pkg.dev/robusta-development/development"
 IMAGE_NAME="python-flask-otel"
-IMAGE_TAG="2.1"
+IMAGE_TAG="2.2"
 FULL_IMAGE="${REGISTRY}/${IMAGE_NAME}:${IMAGE_TAG}"
 LOCAL_IMAGE="holmes-test/${IMAGE_NAME}:${IMAGE_TAG}"
 
@@ -33,3 +33,4 @@ echo "  - OpenTelemetry API & SDK 1.37.0"
 echo "  - OpenTelemetry Flask instrumentation 0.58b0"
 echo "  - OpenTelemetry OTLP gRPC exporter 1.37.0"
 echo "  - Requests 2.32.3"
+echo "  - Prometheus Client 0.21.1"

tests/llm/fixtures/test_ask_holmes/124_checkout_latency_prometheus/test_case.yaml

@@ -1,5 +1,5 @@
 user_prompt:
-- "The checkout service in namespace app-124 is experiencing high latency. Investigate why."
+- "The /checkout endpoint in namespace app-124 is experiencing high latency. Investigate why."
 #  Note telling holmes to focus on http_request_duration_seconds_bucket metric passes with sonnet - 'The checkout service in namespace app-124 is experiencing high latency. Investigate why. USE prometheus and http_request_duration_seconds_bucket'
 
 expected_output: