Replace error page animations by static images

[baszoetekouw]

The animated error pages currently use the lottie-player module, which is quite large and can be run with a strict CSP (see #764).

Therefore, we should replace the animated pages by a nice static images.

The following pages should be fixed:

• client/src/pages/DeadEnd.jsx --> https://sram.surf.nl/dead-end
• client/src/pages/NotFound.jsx --> https://sram.surf.nl/anythinghere
• client/src/pages/ServerError.jsx --> https://sram.surf.nl/error
• client/src/pages/ServiceDenied.jsx --> https://sram.surf.nl/service-denied?service_name=Pippie+Langkous&error_status=4&entity_id=Kakelbont&issuer_id=hoipiepeloi&user_id=pippie%40sram.surf.nl

@FlorisFokkinga could you propose what these pages should look like?

[baszoetekouw]

Is /dead-end even used anymore? What is dat supposed to do?

[oharsta]

See also e0de2fd. I have put the images in the original lotties folder to find them easily. Once the final images are picked, we can move them.

[FlorisFokkinga]

It is permitted to use animated SVG files for this.

[FlorisFokkinga]

I've spent 15 minutes searching for OK looking CSS animated SVGs, didn't find any.

[FlorisFokkinga]

Please (re)center the 404 page: https://test.sram.surf.nl/anythinghere

[oharsta]

Re-centered 404 in 81e7420