Replace line on testimonial link with an icon?

i think it will be the best if you change the testimonial.php

copy a testimonial.php to your child-theme / shortcodes folder
if this does not exist – create one.
the file to copy is in enfold/config-templatebuilder/avia-shortcodes/

and add this to your child-theme functions.php :

add_filter('avia_load_shortcodes', 'avia_include_shortcode_template', 15, 1);
function avia_include_shortcode_template($paths)
{
  $template_url = get_stylesheet_directory();
      array_unshift($paths, $template_url.'/shortcodes/');

  return $paths;
}

now the copy will be used instead of the parent-theme shortcode.

see line : 420/421:

if($link)	$output .= "<span class='hidden avia-testimonial-markup-link'  {$markup_url}>{$link}</span>";
if($link)	$output .= " &ndash; <a class='aviablank avia-testimonial-link' href='{$link}' >{$linktext}</a>";

here is your “-” that – delete it to have:

if($link)	$output .= "<span class='hidden avia-testimonial-markup-link'  {$markup_url}>{$link}</span>";
if($link)	$output .= " <a class='aviablank avia-testimonial-link' href='{$link}' >{$linktext}</a>";

if you like to insert later an icon you can place it then via pseudoclass :before f.e:

.avia-testimonial-link::before {
    content: "\e822 \00a0";
    font-family: entypo-fontello;
}

Result here: Link