Add beginTime to emitter to fix emitter position

[rcole34]

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Issue Link 🔗

• Is this a bug fix or a feature? Bug Fix
• Does it break any existing functionality? No, although it may change some existing functionality (to work how it's supposed to work)

Goals of this PR 🎉

• Why is the change important? Prevents confetti from appearing in the middle of the screen instead of at the emitter point
• What does this fix? See videos below (note in the before confetti appears elsewhere on the screen at first instead of just at the emitter point
• How far has it been tested? Enough to see that it works 🙂 . I came to this solution through the following excerpt from a NSHipster article (https://nshipster.com/caemitterlayer/):

  The central problem is that Core Animation operates on its own timeline, which doesn’t always comport with our own understanding of time.
  For instance, if you neglect to initialize the beginTime of the emitter layer with CACurrentMediaTime() right before it’s displayed, it’ll render with the wrong time space.

Before:

After:

How Has This Been Tested 🔍

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• User Interface Testing
• Application Testing

Test Configuration 👾

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• iOS version || MacOSX version

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