Add Roblox Secrets Support for API Key

[LifeBlox]

Roblox recently released Secrets Store which allows developers to create secret variables for use within HTTPService in their game.

It would be cool if the Game Analytics SDK allowed for Secrets to be passed in-place of plain-text API keys for better security.

[OutOfBears]

I've attempted to look into adding this functionality, but while reading through the code it seemingly generates a hmac hash of the payload and the secret in Lua and attaches it as a header before sending the request, to authenticate the request. This implementation will not work with secrets store as it will not let you read the value in luau.