Fix ext. tools failing with a [{Required,Optional}Api] ApiContainer

Author: YoshiRulz

src/BizHawk.Client.Common/Api/BasicApiProvider.cs

@@ -13,7 +13,12 @@ public class BasicApiProvider : IExternalApiProvider
 
 		public BasicApiProvider(ApiContainer apiContainer) => Container = apiContainer;
 
-		public object? GetApi(Type t) => Container.Libraries.TryGetValue(t, out var api) ? api : null;
+		public object? GetApi(Type t)
+			=> Container.Libraries.TryGetValue(t, out var api)
+				? api
+				: t == typeof(ApiContainer)
+					? Container
+					: null;
 
 		public bool HasApi(Type t) => Container.Libraries.ContainsKey(t);
 	}