refactor: change to 'png' file setup

Author: hyfydistro

public/assets/images/og-scs.jpg public/assets/images/og-scs.png

@@ -18,14 +18,14 @@
   <meta property="og:title" content="Super Comic Slicer - your webcomic utility for cropping! Plus scaling!" />
   <meta property="og:site_name" content="Super Comic Slicer" />
   <meta property="og:type" content="website" />
-  <meta property="og:image" content="/assets/images/og-scs.jpg" />
+  <meta property="og:image" content="/assets/images/og-scs.png" />
   <meta property="og:image:type" content="image/jpeg" />
   <meta property="og:image:width" content="400" />
   <meta property="og:image:height" content="210" />
   <meta property="og:image:alt" content="Super Comic Slicer" />
   <meta property="og:url" content="https://supercomicslicer.netlify.app/" />
   <meta property="twitter:creator" content="@spectredox" />
-  <meta property="twitter:image" content="/assets/images/og-scs.jpg" />
+  <meta property="twitter:image" content="/assets/images/og-scs.png" />
   <meta property="twitter:card" content="summary_large_image" />
   <meta property="og:description"
       content="A web application that crop, divide and scale your really long comic page." />