[Glitch] Rename JSX files with proper .jsx extension

Port 44a7d87cb1 to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/components/check.jsx

@@ -0,0 +1,9 @@
+import React from 'react';
+
+const Check = () => (
+  <svg width='14' height='11' viewBox='0 0 14 11'>
+    <path d='M11.264 0L5.26 6.004 2.103 2.847 0 4.95l5.26 5.26 8.108-8.107L11.264 0' fill='currentColor' fillRule='evenodd' />
+  </svg>
+);
+
+export default Check;