Diagnostics Improvements - Add readRequestsFallbackenabled flag to Client Side request diagnostics and Client Telemetry

Add this flag to Client Side request diagnostics -

```
/**
* Sets whether to allow for reads to go to multiple regions configured on an account of Azure Cosmos DB service.
*

* DEFAULT value is true.
*

* If this property is not set, the default is true for all Consistency Levels other than Bounded Staleness,
* The default is false for Bounded Staleness.
* 1. {@link #endpointDiscoveryEnabled} is true
* 2. the Azure Cosmos DB account has more than one region
*
* @param readRequestsFallbackEnabled flag to enable reads to go to multiple regions configured on an account of
* Azure Cosmos DB service.
* @return current CosmosClientBuilder
*/
public CosmosClientBuilder readRequestsFallbackEnabled(boolean readRequestsFallbackEnabled) {
this.readRequestsFallbackEnabled = readRequestsFallbackEnabled;
return this;
}
```