feat(jmt): update getShowInterstitialTime start metric

[gabrielchl]

COMPLETES https://jira-eng-gpk2.cisco.com/jira/browse/SPARK-782063

This pull request addresses

inaccurate starting timestamp used for getShowInterstitialTime

by making the following changes

changing the start of this latency from 'client.interstitial-window.start-launch' to 'internal.client.meeting.interstitial-window.showed', which is the "end point" of "getClickToInterstitial"

this will make showInterstitialTime a bit shorter (around .5 - 1s)

tested with guest join, sign in join and x-launch join

Change Type

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update
• Tooling change
• Internal code refactor

The following scenarios were tested

< ENUMERATE TESTS PERFORMED, WHETHER MANUAL OR AUTOMATED >

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  • Defect fix
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[gabrielchl]

debugging issue where client.call.initiated seems to not be sent