destructuring.adoc: fix typo (double final dot)

Author: Grahack

content/guides/destructuring.adoc

@@ -184,7 +184,7 @@ You can combine any or all of these techniques at the same time at your discreti
 ;= The fruits after them are (peach pear lemon)
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-Destructuring can also be nested to get access to arbitrary levels of sequential structure.. Let's go back to our vector from the very beginning, `my-line`.
+Destructuring can also be nested to get access to arbitrary levels of sequential structure. Let's go back to our vector from the very beginning, `my-line`.
 
 [source,clojure]
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