Replace foreach filter with LINQ Any in HasAmbientCommandPrefix

Author: carldebilly

src/Repl.Core/CoreReplApp.Interactive.cs

@@ -1621,15 +1621,8 @@ private bool HasAmbientCommandPrefix(string token, StringComparison comparison)
 			return true;
 		}
 
-		foreach (var name in _options.AmbientCommands.CustomCommands.Keys)
-		{
-			if (name.StartsWith(token, comparison))
-			{
-				return true;
-			}
-		}
-
-		return false;
+		return _options.AmbientCommands.CustomCommands.Keys
+			.Any(name => name.StartsWith(token, comparison));
 	}
 
 	private static bool TryClassifyTemplateSegment(