Remove background-image when image is loaded

[luukbrauckmann]

When loading in a png the scaled down background-image placeholder is visible through the main image. This needs to be removed when the main image is loaded.

See possible solution:

• https://github.com/voorhoede/fellow-digitals-website/blob/23-create-badges-parade/src/blocks/ImageBlock/Image.client.ts
• https://github.com/voorhoede/fellow-digitals-website/blob/db02f6239548ab036622d0ee1c2cc626279bc2a8/src/blocks/ImageBlock/Image.astro#L31