Ported missing System.Threading.Channels comments from source to Docs (#2308)

* Ported missing System.Threading.Channels comments from source to Docs

* Update xml/System.Threading.Channels/ChannelReader`1.xml

Co-Authored-By: carlossanlop <1175054+carlossanlop@users.noreply.github.com>

* Update xml/System.Threading.Channels/Channel`2.xml

Co-Authored-By: carlossanlop <1175054+carlossanlop@users.noreply.github.com>

* Update xml/System.Threading.Channels/Channel`2.xml

Co-Authored-By: carlossanlop <1175054+carlossanlop@users.noreply.github.com>

* Update xml/System.Threading.Channels/Channel`2.xml

Co-Authored-By: carlossanlop <1175054+carlossanlop@users.noreply.github.com>

* Update xml/System.Threading.Channels/Channel`2.xml

Co-Authored-By: carlossanlop <1175054+carlossanlop@users.noreply.github.com>

* Update xml/System.Threading.Channels/Channel`2.xml

Co-Authored-By: carlossanlop <1175054+carlossanlop@users.noreply.github.com>

* fix link

Author: carlossanlop

xml/System.Threading.Channels/ChannelReader`1.xml

@@ -81,8 +81,8 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <summary>Creates an <see cref="T:System.Collections.Generic.IAsyncEnumerable`1" /> that enables reading all of the data from the channel.</summary>
+        <returns>An <see cref="T:System.Collections.Generic.IAsyncEnumerable`1" /> that enables reading all of the data from the channel.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -163,4 +163,4 @@
       </Docs>
     </Member>
   </Members>
-</Type>
+</Type>

xml/System.Threading.Channels/Channel`2.xml

@@ -63,9 +63,9 @@
         <Parameter Name="channel" Type="System.Threading.Channels.Channel&lt;TWrite,TRead&gt;" />
       </Parameters>
       <Docs>
-        <param name="channel">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="channel">The <see cref="T:System.Threading.Channels.Channel`2" /> being cast.</param>
+        <summary>Implicit cast from a <see cref="T:System.Threading.Channels.Channel`2" /> to its readable half.</summary>
+        <returns>The readable half.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -89,9 +89,9 @@
         <Parameter Name="channel" Type="System.Threading.Channels.Channel&lt;TWrite,TRead&gt;" />
       </Parameters>
       <Docs>
-        <param name="channel">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="channel">The <see cref="T:System.Threading.Channels.Channel`2" /> being cast.</param>
+        <summary>Implicit cast from a <see cref="T:System.Threading.Channels.Channel`2" /> to its writable half.</summary>
+        <returns>The writable half.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -140,4 +140,4 @@
       </Docs>
     </Member>
   </Members>
-</Type>
+</Type>