Configure Telemetry for Span Metrics Generation and add Visualizations

[BlairCurrey]

Context

We investigated different methods for measuring gql resolver durations and found generating metrics from our spans to be the best solution. This branch includes a working configuration for the local environment: https://github.com/interledger/rafiki/tree/bc/2802/investigate-span-metrics-generator

Todos

• configure tempo/promethus for metric generation (see bc/2802/investigate-span-metrics-generator)
• Create visualization(s) based on the traces_spanmetrics_latency_bucket metric and relevant span_labels (mutation CreateQuote for example) to visualize the resolver durations.
  • could have an aggregated view where we group by resolvers and/or individual visualizations for each resolver