Update favicon and logo

[rjwills28]

I've updated the the favicon and logo based on the updated image provided in #54. As far as I can tell, the favicon already appears on the documentation webpage (see https://diamondlightsource.github.io/coniql/main/index.html), so nothing more to do there.

[aawdls]

Does this get served at /favicon.ico for coniql.diamond.ac.uk or just for the docs?

[AlexanderWells-diamond]

This will not get served in the main application. The image only exists in the docs/images directory and I don't think it ends up in the runtime image.

The only human-readable web endpoint Coniql really exposes is /ws, and that's only when we turn on Graphiql. I don't think we can actually modify that page, as it looks like the favicon is somehow baked in to the Javascript or CSS - at least, there's no explicit request to the server for the favicon.

I can see the appeal in including it in the actual application. I can also see that there's no real point in doing so, at least at present, as there will be no-one to view it.

[aawdls]

Yep agree