Docs: use a working ical example for create_schedule

src/schema_formats/HTML/HTML.xsl

@@ -197,7 +197,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
         <xsl:text>&gt;</xsl:text>
         <xsl:call-template name="newline"/>
         <xsl:choose>
-          <xsl:when test="name() = 'help_response' or name() = 'p'">
+          <xsl:when test="name() = 'help_response' or name() = 'p' or name() = 'icalendar'">
             <!-- Special case certain responses to preserve whitespace. -->
             <xsl:variable name="string" select="func:string-trim-nl(text())"/>
             <xsl:if test="string-length($string) &gt; 0">

src/schema_formats/XML/GMP.xml.in

@@ -4994,11 +4994,17 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
       <summary>Create a schedule</summary>
       <request>
         <create_schedule>
-          <name>Every day</name>
-          <timezone>UTC</timezone>
+          <name>On the third Wednesday of every month</name>
+          <timezone>America/New_York</timezone>
           <icalendar>
-            <truncated>...</truncated>
-            DTSTART;TZID=/UTC:20200603T162600
+BEGIN:VCALENDAR
+VERSION:2.0
+PRODID:-//XXX//NONSGML//EN
+BEGIN:VEVENT
+DTSTART;TZID="America/New_York":20221214T000100
+RRULE:FREQ=MONTHLY;BYDAY=3WE;
+END:VEVENT
+END:VCALENDAR
           </icalendar>
         </create_schedule>
       </request>