[gateway] Remove signalfx receiver from gateway configs

[crobert-1]

Description:

Follow up to #6837, remove the signalfx receiver from default gateway configurations.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 37.96%. Comparing base (ae441c4) to head (609aae0).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6887      +/-   ##
==========================================
+ Coverage   37.95%   37.96%   +0.01%     
==========================================
  Files         367      367              
  Lines       25743    25743              
==========================================
+ Hits         9770     9774       +4     
+ Misses      15161    15159       -2     
+ Partials      812      810       -2     

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[Copilot]

Pull Request Overview

This PR replaces the SignalFx receiver with an HTTP forwarder extension in the default gateway configuration. This is a breaking change that removes the SignalFx receiver from pipelines and introduces a new http_forwarder/signalfx extension to handle SignalFx format data.

• Removed the signalfx receiver from the gateway configurations
• Added http_forwarder/signalfx extension to forward SignalFx format data
• Removed logs/signalfx pipeline from all configurations
• Removed signalfx receiver from the metrics pipeline

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/general/default_config_test.go	Updated test expectations to reflect new extension and removed SignalFx receiver/pipeline
packaging/technical-addon/Splunk_TA_otel/configs/ta-gateway-config.yaml	Added http_forwarder/signalfx extension, removed signalfx receiver and logs/signalfx pipeline
deployments/nomad/otel-gateway.nomad	Added http_forwarder/signalfx extension with include_metadata, removed signalfx receiver and logs/signalfx pipeline
cmd/otelcol/fips/config/gateway_config.yaml	Added http_forwarder/signalfx extension, removed signalfx receiver, logs/signalfx pipeline, and exporter comments
cmd/otelcol/config/collector/gateway_config.yaml	Added http_forwarder/signalfx extension, removed signalfx receiver, logs/signalfx pipeline, and exporter comments
.chloggen/remove_sfx_receiver_gateway.yaml	Added changelog entry documenting the breaking change

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[Copilot]

Pull Request Overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

packaging/technical-addon/Splunk_TA_otel/configs/ta-gateway-config.yaml:138

• The service extensions list was not updated to include the new http_forwarder/signalfx extension. This means the extension is configured but won't be active, breaking SignalFx data forwarding. Add http_forwarder/signalfx to the extensions list.

  extensions: [headers_setter, health_check, http_forwarder, zpages]

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The comments in the agent config has to be updated as well

[dmitryax]

LGTM