[SVLS-3545] Add Serverless metric origins to dogstatsd

[duncanpharvey]

What does this PR do?

Adds metric origins for Serverless. This will affect the Lambda Extension and Serverless Compatibility Layer.

Currently all metrics (custom and standard) are bucketed into the serverless origin product. At the moment, we just want to be able to differentiate custom metrics by their source.

Motivation

https://datadoghq.atlassian.net/browse/SVLS-3545

Additional Notes

Migrated from DataDog/libdatadog#876

• All Metrics sent from this DogStatsD server will have Origin Product: Serverless
• Origin Subproduct (aka OriginCategory) maps based on metric tag
  • origin: appservice -> AppServicesMetrics
  • origin: cloudrun -> CloudRunMetrics
  • origin: containerapp -> ContainerAppMetrics
  • origin: azurefunction -> AzureFunctionsMetrics
  • function_arn: * -> LambdaMetrics
• Product Detail (aka OriginService) maps based on metric name
  • datadog.* -> None
  • runtime.* -> ServerlessRuntime
  • jvm.* -> ServerlessRuntime
  • aws.lambda.* -> ServerlessEnhanced
  • gcp.run.* -> ServerlessEnhanced
  • azure.app_service.* -> ServerlessEnhanced waiting to add until enhanced metrics with this prefix are created
  • azure.app_containerapp.* -> ServerlessEnhanced waiting to add until enhanced metrics with this prefix are created
  • azure.functions.* -> ServerlessEnhanced waiting to add until enhanced metrics with this prefix are created
  • Else -> ServerlessCustom

Describe how to test/QA your changes

[duncanpharvey]

Still needs logic to set the metric metadata differently depending on whether the metric is a runtime metric (prefix runtime.* or jvm.*) or a custom metric (all other prefixes)