Show the current version somewhere

[Tobi696]

Describe the feature or enhancement

It would be nice to see the currently running version of umami somewhere for self-hosted users.

[franciscao633]

We should probably do this. will add a tag.

[Nambers]

for ref similar to #3771

[jlar0che]

This used to exist in version 2. Very helpful when checking what version you currently have vs what is the newest available.