Add the new logotype to the platform

[kallewesterling]

As we now have a new logotype for the platform, we should make sure that it's included in all places where we currently just have the name or a placeholder logotype.

The final files have been uploaded to the Sharepoint, see:

• unzipped directory: https://thealanturininstitute.sharepoint.com/:f:/s/tea-dh/EgHW_5RNkXlJnNT3hTjwnFsBHQGQhCo9_7vWq5_Oh3_QrQ?e=LMGBgG
• zip file: https://thealanturininstitute.sharepoint.com/:u:/s/tea-dh/EQpdmDRoHrBHsimfksEn5MoBUSgEE2GRsdMHr6qjbusmzg?e=2CtIxT

Related issue:

• [X] https://github.com/alan-turing-institute/AssurancePlatform/issues/342