Broken links (dotnet#3896)

* fix broken link

* fix broken link

* encase invalid URL

Author: mairaw

xml/System.Web.Services.Protocols/SoapRpcMethodAttribute.xml

@@ -127,7 +127,7 @@
       </ReturnValue>
       <Docs>
         <summary>Gets or sets the <see langword="SOAPAction" /> HTTP header field of the SOAP request.</summary>
-        <value>The <see langword="SOAPAction" /> HTTP header field of the SOAP request. The default is http://tempuri.org/MethodName where MethodName is the name of the XML Web service method.</value>
+        <value>The <see langword="SOAPAction" /> HTTP header field of the SOAP request. The default is <c>http://tempuri.org/MethodName</c> where MethodName is the name of the XML Web service method.</value>
         <remarks>
           <format type="text/markdown"><![CDATA[  
   

xml/System.Web.UI.WebControls/WebControl.xml

@@ -1132,7 +1132,7 @@ void Application_Start(object sender, EventArgs e)
         </remarks>
         <altmember cref="P:System.Web.UI.Control.EnableTheming" />
         <altmember cref="P:System.Web.UI.WebControls.WebControl.SkinID" />
-        <related type="Article" href="https://docs.microsoft.com/previous-versions/aspnet/ykzx33wh(v=vs.100)(v=vs.100)">ASP.NET Themes Overview</related>
+        <related type="Article" href="https://docs.microsoft.com/previous-versions/aspnet/ykzx33wh(v=vs.100)">ASP.NET Themes Overview</related>
         <related type="Article" href="https://docs.microsoft.com/previous-versions/aspnet/zt27tfhy(v=vs.100)">Developing Custom ASP.NET Server Controls</related>
       </Docs>
     </Member>

xml/System.Web.UI/DataSourceControl.xml

@@ -619,7 +619,7 @@
  ]]></format>
         </remarks>
         <exception cref="T:System.NotSupportedException">An attempt was made to set the value of the <see cref="P:System.Web.UI.DataSourceControl.SkinID" /> property.</exception>
-        <related type="Article" href="https://docs.microsoft.com/previous-versions/aspnet/ykzx33wh(v=vs.100)(v=vs.100)">ASP.NET Themes Overview</related>
+        <related type="Article" href="https://docs.microsoft.com/previous-versions/aspnet/ykzx33wh(v=vs.100)">ASP.NET Themes Overview</related>
       </Docs>
     </Member>
     <Member MemberName="System.ComponentModel.IListSource.ContainsListCollection">