Fix some unfriendly behavior in Favicon#create(Path)

api/src/main/java/com/velocitypowered/api/util/Favicon.java

@@ -93,7 +93,11 @@ public final class Favicon {
    */
   public static Favicon create(Path path) throws IOException {
     try (InputStream stream = Files.newInputStream(path)) {
-      return create(ImageIO.read(stream));
+      BufferedImage image = ImageIO.read(stream);
+      if (image == null) {
+        throw new IOException("Unable to read the image.");
+      }
+      return create(image);
     }
   }
 }