Hi there, I have found it so thought should let you know as well 
It is under featured-product.liquid in dawn theme.
where it says
wrap the whole div in to href as in
in short please see how I wrapped it into href below . Also before making any change please keep a copy of the whole featured-product.liquid. Normally I save it into notepad before making any change so I can revert to that in case the code does not work. Here is the solution.
{% render 'product-thumbnail',
media: media,
position: forloop.index,
loop: section.settings.enable_video_looping,
modal_id: section.id,
xr_button: false,
media_width: media_width,
media_fit: section.settings.media_fit,
constrain_to_viewport: section.settings.constrain_to_viewport
%}
It should work as I just checked it on my site. Please mark it as a solution if it does so others can know it as well.