Fix typo in CosmosDB README (#2177)

src/HealthChecks.CosmosDb/README.md

@@ -38,7 +38,7 @@ void Configure(IHealthChecksBuilder builder)
             ApplicationRegion = Regions.EastUS2,
         }));
     builder.AddHealthChecks().AddAzureCosmosDB(
-        optionsFactory: sp => new CosmosDbHealthCheckOptions()
+        optionsFactory: sp => new AzureCosmosDbHealthCheckOptions()
         {
             DatabaseId = "demo"
         });
@@ -48,5 +48,3 @@ void Configure(IHealthChecksBuilder builder)
 ### Breaking changes
 
 In the prior releases, `CosmosDbHealthCheck` was a part of `HealthChecks.CosmosDb` package. It had a dependency on not just `Microsoft.Azure.Cosmos`, but also `Azure.Data.Tables`. The packages have been split to avoid bringing unnecessary dependencies. Moreover, `CosmosDbHealthCheck` was letting the users specify how `CosmosClient` should be created (from raw connection string or from endpoint and managed identity credentials), at a cost of maintaining an internal, static client instances cache. Now the type does not create client instances nor maintain an internal cache and **it's the caller responsibility to provide the instance of `CosmosClient`** (please see [#2040](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/issues/2040) for more details). Since Azure SDK recommends treating clients as singletons <see href="https://devblogs.microsoft.com/azure-sdk/lifetime-management-and-thread-safety-guarantees-of-azure-sdk-net-clients/"/> and client instances can be expensive to create, it's recommended to register a singleton factory method for Azure SDK clients. So the clients are created only when needed and once per whole application lifetime.
-
-