Update IHost.xml (#7508)

Add apostrophe for possessive. Make verb tenses consistently simple present tense.

Author: GregoryShields

xml/Microsoft.Extensions.Hosting/IHost.xml

@@ -45,7 +45,7 @@
         <ReturnType>System.IServiceProvider</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>The programs configured services.</summary>
+        <summary>The program's configured services.</summary>
         <value>To be added.</value>
         <remarks>To be added.</remarks>
       </Docs>
@@ -74,7 +74,7 @@
       </Parameters>
       <Docs>
         <param name="cancellationToken">Used to abort program start.</param>
-        <summary>Start the program.</summary>
+        <summary>Starts the program.</summary>
         <returns>A <see cref="T:System.Threading.Tasks.Task" /> that will be completed when the <see cref="T:Microsoft.Extensions.Hosting.IHost" /> starts.</returns>
         <remarks>To be added.</remarks>
       </Docs>