Update hybrid.md

Author: Rick-Anderson

aspnetcore/performance/caching/hybrid.md

@@ -143,7 +143,7 @@ For more information, see the [HybridCache serialization sample app](https://git
 
 ## Cache storage
 
-By default `HybridCache` uses <xref:System.Runtime.Caching.MemoryCache> for its primary cache storage. Cache entries are stored in-process, so each server has a separate cache that is lost whenever the server process is restarted. For secondary out-of-process storage, such as Redis or SQL Server, `HybridCache` uses [the configured `IDistributedCache` implementation](xref:performance/caching/distributed), if any. But even without an `IDistributedCache`implementation, the `HybridCache` service still provides in-process caching and stampede protection.
+By default `HybridCache` uses <xref:System.Runtime.Caching.MemoryCache> for its primary cache storage. Cache entries are stored in-process, so each server has a separate cache that is lost whenever the server process is restarted. For secondary out-of-process storage, such as Redis or SQL Server, `HybridCache` uses [the configured `IDistributedCache` implementation](xref:performance/caching/distributed), if any. But even without an `IDistributedCache`implementation, the `HybridCache` service still provides in-process caching and [stampede protection](https://en.wikipedia.org/wiki/Cache_stampede).
 
 ## Optimize performance