docs/website/download.html: fix latest LTS version number

Latest is naturally .3, not .1

Reported-by: Thomas De Schampheleire <patrickdepinguin@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

docs/website/download.html

@@ -8,7 +8,7 @@
     <div class="panel-heading">Download</div>
     <div class="panel-body">
 
-      <h3 style="text-align: center;">Latest long term support release: <b>2018.02.1</b></h3>
+      <h3 style="text-align: center;">Latest long term support release: <b>2018.02.3</b></h3>
 
       <div class="row mt centered">
 	<div class="col-sm-6">