Request submitting a review on app stores

**What problem are you trying to solve?**
Reviews of MetaMask on the chrome store are quite old and some are unrelated to the product (bad reviews due to phishing detect blocking their site, etc.)

**Describe the solution you'd like**
Like many apps out there, if someone uses MetaMask often, maybe after the 10th transaction they get a "Like MetaMask? Let others known why".

**Additional context**
This could be used for mobile too, and might help keep a constant feedback loop on recent updates and features we roll out.

No files, tests, or entry points are named. Start by locating where transaction completion is handled and research the supported review-request APIs for the Chrome store and mobile platforms. Done means defining and implementing an agreed prompt policy for frequent users without disrupting normal transaction flows.

Written by the indexing model from the issue text.