Fix CA1841

.editorconfig

@@ -741,6 +741,9 @@ dotnet_diagnostic.CA1839.severity = warning
 # Use Environment.CurrentManagedThreadId instead of Thread.CurrentThread.ManagedThreadId.
 dotnet_diagnostic.CA1840.severity = warning
 
+# Prefer Dictionary Contains methods.
+dotnet_diagnostic.CA1841.severity = warning
+
 # Do not use 'WhenAll' with a single task.
 dotnet_diagnostic.CA1842.severity = warning
 

OpenRA.Mods.Common/Lint/CheckVoiceReferences.cs

@@ -66,7 +66,7 @@ namespace OpenRA.Mods.Common.Lint
 						if (string.IsNullOrEmpty(voice))
 							continue;
 
-						if (!soundInfo.Voices.Keys.Contains(voice))
+						if (!soundInfo.Voices.ContainsKey(voice))
 							emitError($"Actor {actorInfo.Name} using voice set {voiceSet} does not define {voice} voice required by {traitInfo}.");
 					}
 				}