fix(analytics): add validation for flushInterval

[5d]

Description of changes

• instead of using setInterval, update Analytics EventBuffer to use setTimeout for perodic event submission jobs.
  • note on behavior change:
    • previously: the action callback set with setInterval will reliably activate at regular intervals, each time spanning the duration specified by flushInterval.
    • with this change: the action callback set with setTimeout will wait for the completion previous callback, and then initiates after flushInterval period of time.
• add validation check on Analytics event buffer's flushInterval.
  • it should greater than or equal to the min value (100ms).

Issue #, if available

Description of how you validated changes

• unit test cases added

Checklist

• PR description included
• yarn test passes
• Tests are changed or added
• Relevant documentation is changed or added (and PR referenced)

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