Remove unneeded og:image:secure_url from social.html
The image is always available over HTTPS anyway
<meta property="og:title" content="{{ page.title | default: site.title | smartify }}">
<meta property="og:description" content="{{ page.description | default: site.description | smartify }}">
<meta property="og:type" content="website">
-<meta property="og:image" content="{{ site.url | replace: 'https://', 'http://' | append: site.social_image_path }}">
-<meta property="og:image:secure_url" content="{{ site.url | append: site.social_image_path }}">
+<meta property="og:image" content="{{ site.url | append: site.social_image_path }}">
<meta property="og:image:type" content="image/png">
<meta property="og:image:width" content="1200">
<meta property="og:image:height" content="630">