Remove support for serverless functions

[joe-elliott]

Currently our codebase supports AWS Lambda and GCP Cloud Run. However, we have recently found that our AWS runtime has been deprecated and the team has no bandwidth to continue maintaining this functionality. We are also generally unsure of the value of serverless and if it actually provides the presumed reduced latency at a lower cost.

Opening this issue as an opportunity for community members to express the desire to keep or maintain Tempo's serverless functionality. As of now, our position is to remove it.

[edgarkz]

I haven't configured it since the Tempo 2.0 version, as I found that the standard Kubernetes HPA scaling works well for our needs.

[github-actions]

This issue has been automatically marked as stale because it has not had any activity in the past 60 days.
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[electron0zero]

serverless functions will be deprecated and deleted in the tempo next release, they are now marked as deprecated.