chore: Add totalSubSteps property and funnelStepError event

[connorlanigan]

Description

This PR adds the new event funnelStepError, which is used to emit a metric about an error that relates to a whole step, usually an Alert outside of a container. It differs from funnelSubStepError, which is for errors inside a substep like a container, and from funnelError, which is more generic.

Related links, issue #, if available: CR-97002073

How has this been tested?

Review checklist

The following items are to be evaluated by the author(s) and the reviewer(s).

Correctness

• Changes include appropriate documentation updates.
• Changes are backward-compatible if not indicated, see CONTRIBUTING.md.
• Changes do not include unsupported browser features, see CONTRIBUTING.md.
• Changes were manually tested for accessibility, see accessibility guidelines.

Security

• If the code handles URLs: all URLs are validated through the checkSafeUrl function.

Testing

• Changes are covered with new/existing unit tests?
• Changes are covered with new/existing integration tests?

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[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (0df2a92) 93.46% compared to head (c480128) 93.46%.

Additional details and impacted files

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  Coverage   93.46%   93.46%           
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  Files         623      623           
  Lines       16733    16733           
  Branches     5527     5527           
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  Hits        15639    15639           
  Misses       1021     1021           
  Partials       73       73           

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[just-boris]

Approved, but I need to understand the context better.

This PR adds events but they are never called. Is this coming in the future PRs?

[connorlanigan]

This PR adds events but they are never called. Is this coming in the future PRs?

Yes. There will be a separate PR to call the new funnelStepError event, and another PR to calculate the value for totalSubSteps.