[4.3] Fix error from #39537 [a11y] (#40323)

You can't have two buttons with the same text that do different things. I am assuming that this change was made in error by @wilsonge in #39537

### Joomla 4.29

### Joomla 4.3 before this PR

### Joomla 4.3 after this PR

Co-authored-by: Quy <[email protected]>

Author: brianteeman

administrator/components/com_installer/src/View/Update/HtmlView.php

@@ -128,7 +128,7 @@ protected function addToolbar()
                 ->icon('icon-upload');
         }
 
-        $toolbar->standardButton('search', 'COM_INSTALLER_TOOLBAR_UPDATE', 'update.find')
+        $toolbar->standardButton('search', 'COM_INSTALLER_TOOLBAR_FIND_UPDATES', 'update.find')
             ->listCheck(false)
             ->icon('icon-refresh');