Fix url

Author: sago35

static/index.html

@@ -9,15 +9,15 @@
     <meta property="og:url" content="https://sago35.github.io/koebiten/">
     <meta property="og:title" content="koebiten wasm">
     <meta property="og:description" content="Koebiten is a 2D game engine that runs on TinyGo. It’s inspired by Ebitengine and is characterized by its simple API.">
-    <meta property="og:image" content="https://sago35.github.io/koebiten/ogp.jpg">
+    <meta property="og:image" content="https://sago35.github.io/koebiten/ogp.png">
     <meta property="og:site_name" content="koebiten wasm">
     <meta property="og:locale" content="ja_JP">
 
     <meta name="twitter:card" content="summary_large_image">
     <meta name="twitter:site" content="@sago35tk">
     <meta name="twitter:title" content="koebiten wasm">
     <meta name="twitter:description" content="Koebiten is a 2D game engine that runs on TinyGo. It’s inspired by Ebitengine and is characterized by its simple API.">
-    <meta name="twitter:image" content="https://sago35.github.io/koebiten/ogp.jpg">
+    <meta name="twitter:image" content="https://sago35.github.io/koebiten/ogp.png">
 
     <script src="wasm_exec.js"></script>
     <script type="module" src="main.js"></script>