Use concrete ConcurrentHashSet instead of abstraction for performance (…

…#960)

* Use concrete ConcurrentHashSet instead of abstraction for performance

Calling into an interface when its not necessary will result in poorer performance because the JIT needs to do some type analysis. When it is a concrete type, this is avoided. Since this is an internal field there's no reason to use the abstracted type. 

See https://learn.microsoft.com/en-us/dotnet/fundamentals/code-analysis/quality-rules/ca1859

src/Lucene.Net/Search/ReferenceManager.cs

@@ -56,7 +56,7 @@ protected G Current
 
         private readonly ReentrantLock refreshLock = new ReentrantLock();
 
-        private readonly ISet<ReferenceManager.IRefreshListener> refreshListeners = new ConcurrentHashSet<ReferenceManager.IRefreshListener>();
+        private readonly ConcurrentHashSet<ReferenceManager.IRefreshListener> refreshListeners = new ConcurrentHashSet<ReferenceManager.IRefreshListener>();
 
         private void EnsureOpen()
         {
@@ -367,7 +367,7 @@ public virtual void RemoveListener(ReferenceManager.IRefreshListener listener)
             {
                 throw new ArgumentNullException(nameof(listener), "Listener cannot be null"); // LUCENENET specific - changed from IllegalArgumentException to ArgumentNullException (.NET convention)
             }
-            refreshListeners.Remove(listener);
+            refreshListeners.TryRemove(listener);
         }
     }
 
@@ -396,4 +396,4 @@ public interface IRefreshListener
             void AfterRefresh(bool didRefresh);
         }
     }
-}
+}