Fix Fargate Container Insights: disable RemoveStartTimeAdjustment

The prometheus receiver's RemoveStartTimeAdjustment feature gate was
promoted to beta (enabled by default) in OTel Collector Contrib v0.140.1.
This causes the receiver to no longer set start times on cumulative
metrics, which breaks the cumulativetodelta processor's delta computation.

Without proper start times, cumulativetodelta drops data points, causing
the downstream deltatorate and metricsgeneration processors to produce
no output. This results in pod_cpu_utilization_over_pod_limit and other
computed Fargate metrics not being emitted.

Disable the feature gate to restore the previous behavior. A future
release should migrate to the metricstarttime processor as the
recommended long-term fix.

Ref: open-telemetry/opentelemetry-collector-contrib#43916

Author: mitali-salvi

terraform/eks/container-insights-agent/stateful_set_fargate.yml

@@ -28,7 +28,7 @@ spec:
           command:
             - "/awscollector"
             - "--config=/conf/adot-collector-config.yaml"
-            - "--feature-gates=-processor.resourcedetection.propagateerrors"
+            - "--feature-gates=-processor.resourcedetection.propagateerrors,-receiver.prometheusreceiver.RemoveStartTimeAdjustment"
           env:
             - name: OTEL_RESOURCE_ATTRIBUTES
               value: "ClusterName=${ClusterName}"