Add Floccus Logo on update page

[hartsberger]

Describe the feature you'd like to request

As a followup of my first feature request (#1634)
It would be great when the Floccus logo is shown on the update page.
This way more user would associate the update page with their bookmark sync.
I assume that for many user using floccus is like: setup sync & forget about it. They don't remember the name "Floccus".

Describe the solution you'd like

The headline says: "Floccus wurde aktualisiert "
I would prefere the logo somewhere in the headline or even above.

Describe alternatives you've considered

Explicitly mention somewhere near the headline that Floccus is for bookmark syncing.

[github-actions]

Hello 👋

Thank you for taking the time to open this issue with floccus. I know it's frustrating when software
causes problems. You have made the right choice to come here and open an issue to make sure your problem gets looked at
and if possible solved.
I'm Marcel and I created floccus and have been maintaining it ever since.
I currently work for Nextcloud which leaves me with less time for side projects like this one
than I used to have.
I still try to answer all issues and if possible fix all bugs here, but it sometimes takes a while until I get to it.
Until then, please be patient.
Note also that GitHub is a place where people meet to make software better together. Nobody here is under any obligation
to help you, solve your problems or deliver on any expectations or demands you may have, but if enough people come together we can
collaborate to make this software better. For everyone.
Thus, if you can, you could also have a look at other issues to see whether you can help other people with your knowledge
and experience. If you have coding experience it would also be awesome if you could step up to dive into the code and
try to fix the odd bug yourself. Everyone will be thankful for extra helping hands!
One last word: If you feel, at any point, like you need to vent, this is not the place for it; you can go to the forum,
to twitter or somewhere else. But this is a technical issue tracker, so please make sure to
focus on the tech and keep your opinions to yourself.

I look forward to working with you on this issue
Cheers 💙