Backport of [HCP Telemetry] Move first TelemetryConfig Fetch into the TelemetryConfigProvider into release/1.15.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #18318 to be assessed for backporting due to the inclusion of the label backport/1.15.

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The below text is copied from the body of the original PR.

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Description

This is a follow up refactor for PR #18168

Now that we have the TelemetryConfigProvider that continuously fetches config from HCP, we can skip the deps.go first fetch and leave that work to the Provider.

Changes:

1. The provider will make a first fetch during initialization to see if there is config available.

• If none, it will set defaults and run the provider

2. OTELSink and OTELExporter : Add an interface to disable, as the sink can now be turned on/off based on the config. Metrics will not be recorded if the sink is not enabled.

Testing & Reproduction steps

Links

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• 3810663 - 76d40eb - 17917a1 - e2020e6 - bc356c3 - d3ff4fd - 0fa2160 - 3e7bd17 - d355427 - e67ba41 - 9c8711c - 150fb64 - 1b3d71a - 4769d7b - 89cb0d3 - aa9f8a6 - b11d972 - 2a784ae - 50266bd - 24e9a7f

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR

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[Achooo]

Closing in favour of #18627