Replace setTimeout for polling in TokenRatesController

[NiranjanaBinoy]

Replace setTimeout for polling in updateExchangeRates() in TokenRatesController in a time window of 3 minutes.

[NiranjanaBinoy]

The corresponding PR has to be created in the controller repo.

Since the chrome alarms have to be used only for the extension, we would have to configure them at the API level to differentiate extension using mv3 from mobile and extension using mv2.
Can we introduce a new optional state variable with true value to identify extension with mv3 and use chrome alarms in that case?

Something similar to MetaMask/core#861

[NiranjanaBinoy]

Closing this ticket after a conversation with the core team. Quoting the comment below and link to the chat here

Using setTimeout might be fine for the intervals that are below 5 minutes. That's not awful.
If the service worker restarts every 5 minutes, then the 3-minute intervals will be triggered once every 2.5 minutes on average. That seems fine.
Though I would check to ensure that the update is triggered upon construction as well. If it's only after 3 minutes has elapsed, then it would become a 5 minute timer in practice.