chore: Emit totalSubSteps in funnel metrics

[connorlanigan]

Description

After this PR, each step of a funnel counts how many sub steps it currently has. This value is then emitted as totalSubSteps in the funnelStepStart and funnelStepComplete events.

Related links, issue #, if available: n/a

How has this been tested?

Extended the unit tests

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 coverage: 100.00% and no project coverage change.

Comparison is base (66fc217) 93.48% compared to head (e40efa4) 93.48%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1356   +/-   ##
=======================================
  Coverage   93.48%   93.48%           
=======================================
  Files         624      624           
  Lines       16788    16797    +9     
  Branches     5548     5549    +1     
=======================================
+ Hits        15694    15703    +9     
  Misses       1021     1021           
  Partials       73       73           

Impacted Files	Coverage Δ
...rc/internal/analytics/context/analytics-context.ts	100.00% <ø> (ø)
...internal/analytics/components/analytics-funnel.tsx	100.00% <100.00%> (ø)

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