fix id for excel question

website/templates/_help.html

@@ -118,8 +118,8 @@
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 <div class="accordion-group">
-            <div class="accordion-heading"><a data-toggle="collapse" data-parent="#accordion-faq" href="#faq-18" class="accordion-toggle collapsed">Can I use an Excel spreadsheet instead of Google Spreadsheets?</a></div>
-            <div id="faq-18" style="height: 0px;" class="accordion-body collapse">
+            <div class="accordion-heading"><a data-toggle="collapse" data-parent="#accordion-faq" href="#faq-can-i-use-excel" class="accordion-toggle collapsed">Can I use an Excel spreadsheet instead of Google Spreadsheets?</a></div>
+            <div id="faq-can-i-use-excel" style="height: 0px;" class="accordion-body collapse">
               <div class="accordion-inner">No. TimelineJS uses Google's API to access the data from the Google Spreadsheet. If you want to start your work in Excel and then copy and paste your data into a Google spreadsheet, that’ll work but the likelihood of errors increases.</div>
             </div>
           </div>