Enhancement: Use the `otel_annotation` flag for k8sattributes receiver

[petewall]

For the application observability feature (and anywhere else we're using the k8s attributes processor), we should utilize the otel_annotations flag, which can automatically set the recommended attributes based on well-known otel annotations.

https://grafana.com/docs/alloy/latest/reference/components/otelcol/otelcol.processor.k8sattributes/#extract