[ZF-8408] TYPO in Zend_Captcha_Image Method DocBlock

git-svn-id: http://framework.zend.com/svn/framework/standard/trunk@19271 44c647ce-9c0f-0410-b52a-842ac1e357ba

library/Zend/Captcha/Image.php

@@ -94,7 +94,7 @@ class Zend_Captcha_Image extends Zend_Captcha_Word
 
     /**
      * Image to use as starting point
-     * Default is blank image. If ptovided, should be PNG image.
+     * Default is blank image. If provided, should be PNG image.
      *
      * @var string
      */