Currently, we cannot decode change stream resume tokens in our JavaScript tests. Resume token contain a bunch of information such as timestamp, version, object IDs, transaction-related info etc., and it is key-string encoded. 

It would be very useful to decode this information for assertion and debugging.

We can either port an existing TypeScript or C++ code to JavaScript, or expose/link the relevant server code function to the JavaScript environment in mongo (old) shell that we use for testing.