[NT-980] Updating the Optimizely events dispatch interval

[ifbarrera]

📲 What

Updates the dispatch interval for the DefaultEventDispatcher on Optimizely to 5 seconds to reduce likelihood of backend race condition.

🤔 Why

The default dispatch interval on the DefaultEventDispatcher used by Optimizely to dispatch events and impressions was 60 seconds. This caused a race condition where sometimes the Kickstarter Ruby backend would attempt to send conversion event for an experiment whose "impression" hadn't been dispatched yet from the iOS SDK. By reducing the dispatch interval we hope to mitigate this race condition.

🛠 How

• Added the dispatchTimeInterval as part of the configureOptimizely output.
• set this value to 5 seconds
• added a test

[eoji]

LGTM, but I made it 2 seconds because I was able to complete a pledge in 3 seconds starting from the project page.