At the end of this task the bigtable::Table class will have a member function to read a single row, and the unit tests associated with it.
The member function will use the existing policies to determine whether to retry any RPC requests, and how to backoff the RPC requests.
The member function will return a Row class with all the data in memory.
This function should take both a absl::string_view parameter for the row key and a bigtable::Filter parameter to control the filter expression associated with the request.

Consider splitting this issue if theFilter class is not ready.