Fixing an include to fix the accidental extra space in the img src tag.

[joseph-r-hamilton]

Playing with html-proofer uncovered a bug.

[qwtel]

Hi, thanks for this PR.

I wasn't aware of the {%- endif -%} syntax. Can you provide a link that explains it in detail?

Note that this should not be an issue in production builds (JEKYLL_ENV=production bundle exec jekyll build) though.

EDIT: wow, there's an extra space even in production builds. Thanks again for fixing this!