Add docs for async enumerable extensionn

src/Discord.Net.Core/Extensions/AsyncEnumerableExtensions.cs

@@ -4,19 +4,15 @@ using System.Threading.Tasks;
 
 namespace Discord
 {
+    /// <summary> An extension class for squashing <see cref="IAsyncEnumerable{T}"/>. </summary>
     public static class AsyncEnumerableExtensions
     {
-        /// <summary>
-        /// Flattens the specified pages into one <see cref="IEnumerable{T}"/> asynchronously
-        /// </summary>
-        /// <typeparam name="T"></typeparam>
-        /// <param name="source"></param>
-        /// <returns></returns>
+        /// <summary> Flattens the specified pages into one <see cref="IEnumerable{T}"/> asynchronously. </summary>
         public static async Task<IEnumerable<T>> FlattenAsync<T>(this IAsyncEnumerable<IEnumerable<T>> source)
         {
             return await source.Flatten().ToArray().ConfigureAwait(false);
         }
-
+        /// <summary> Flattens the specified pages into one <see cref="IAsyncEnumerable{T}"/>. </summary>
         public static IAsyncEnumerable<T> Flatten<T>(this IAsyncEnumerable<IEnumerable<T>> source)
         {
             return source.SelectMany(enumerable => enumerable.ToAsyncEnumerable());