Change "Leave a Reply" text in comments box

Hello!

This has been on my list for a while and I thought I would get to it now. I would like to change the comments default intro text from “Leave a reply” to “Leave a comment.” How can I do this? I see various options over the years for customizing this, including making the change in comments.php (I think I found the relevant lines, below) but that is only in the theme file, not child theme, so I am concerned the change will be overwritten next time the theme is updated.

Thanks,
Rob

if(comments_open()){

echo “<div class=’comment_container’>”;
echo “<h3 class=’miniheading’>”.__(‘Leave a Reply’,’avia_framework’).”</h3>”;
echo “<span class=’minitext’>”.__(‘Want to join the discussion?’,’avia_framework’).” <br/>”.__(‘Feel free to contribute!’,’avia_framework’).”</span>”;
comment_form();
echo “</div>”;