feat(websocket_server sink): add simple customizable extra metrics tags for websocket_server

[esensar]

Summary

This adds a new configuration option to websocket_server to enable adding additional tags to metrics generated by this component.

Change Type

• Bug fix
• New feature
• Non-functional (chore, refactoring, docs)
• Performance

Is this a breaking change?

• Yes
• No

How did you test this PR?

Besides the added tests, I have tested Vector with the following config:

sources:
  demo_logs_test:
    type: "demo_logs"
    format: "json"

  mets:
    type: "internal_metrics"

transforms:
  filtered_metrics:
    type: "filter"
    inputs: ["mets"]
    condition: .tags.component_id == "websocket_sink"

sinks:
  websocket_sink:
    inputs: ["demo_logs_test"]
    type: "websocket_server"
    address: "0.0.0.0:1234"
    internal_metrics:
      extra_tags:
        test_extra_tag:
          type: fixed
          value: test_value
        user_auth:
          type: header
          name: Authorization
        client_ip:
          type: ip_address
        full_url:
          type: url
        some_query:
          type: query
          name: last_received
    acknowledgements:
      enabled: false
    encoding:
      codec: "json"

  console:
    inputs: ["filtered_metrics"]
    target: "stdout"
    type: "console"
    acknowledgements:
      enabled: false
    encoding:
      codec: "json"

Does this PR include user facing changes?

• Yes. Please add a changelog fragment based on our guidelines.
• No. A maintainer will apply the "no-changelog" label to this PR.

Checklist

• Please read our Vector contributor resources.
  • make check-all is a good command to run locally. This check is
    defined here. Some of these
    checks might not be relevant to your PR. For Rust changes, at the very least you should run:
    • cargo fmt --all
    • cargo clippy --workspace --all-targets -- -D warnings
    • cargo nextest run --workspace (alternatively, you can run cargo test --all)
• If this PR introduces changes Vector dependencies (modifies Cargo.lock), please
  run dd-rust-license-tool write to regenerate the license inventory and commit the changes (if any). More details here.

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Sponsored by Quad9

[rtrieu]

Some feedback for style consistency.

[esensar]

Some feedback for style consistency.

Thank you!

[rtrieu]

Minor feedback.

[pront]

Thanks @esensar

[rtrieu]

I left a simple non-breaking suggestion.