[REQUIRED] Please fill in the following fields:

• Pre-built SDK from the website or open-source from this repo: Open source from this repo
• Firebase C++ SDK version: 8.9.0
• Problematic Firebase Component: Remote config
• Other Firebase Components in use: None
• Platform you are using the C++ SDK on: Windows, Mac
• Platform you are targeting: desktop

[REQUIRED] Please describe the issue here:

Users % targettig does not seem to work as it should. It rolls a dice every fetch so it does not have any notion of a user or client thus single client can get various configs every fetch

Steps to reproduce:

Configure remote config so it has a user % based condition and serve one config (config A) for 50% of users and the other (config B) for the rest. Fetch the config multiple times.
Expected: A user who got config A keeps getting config A and the one who got config B always gets config B.
Actual: The user who got config A gets config B on subsequent fetch.

Relevant Code: