Revisit ReadThroughput api for single return type

[simplynaveen20]

We have two public api for throughput, one return nullable int and other return ThroughputResponse, they are getting differentiate based on requestOptions.
We did this for simple use case where user will just need call ReadThroughputAsync without requestOption , and if user need the whole response which have other properties in it ,they can pass the requestOption
and it will be in line with our other read responses where one case pass etag and other request options.
Problem here is user working on ThroughputResponse had to pass the requestOptions as we don’t have a default value for it.
Idea here is merging both these api together having default null requestOptions and implicit conversion for int?.

public abstract Task<int?> ReadThroughputAsync(
CancellationToken cancellationToken = default(CancellationToken));

public abstract Task ReadThroughputAsync(
RequestOptions requestOptions,

[deborahc]

+1. Currently you can pass in empty RequestOptions() to see the other properties (MinThroughput, IsReplacePending), which isn't intuitive.

 // Scale down the database to the minimum RU/s. 
var currentThroughput = await partitioningDemoDB.ReadThroughputAsync(requestOptions: new RequestOptions());
int minThroughput = (int)currentThroughput.MinThroughput;
var throughputResponse = await partitioningDemoDB.ReplaceThroughputAsync(minThroughput);