Disable Location Sharing if map_style_url is not provided

### Steps to reproduce

- Remove "map_style_url" from config.json or set it to blank.
- Try to share Location.
- You'll get an error message: "Failed to load map"


### Outcome

#### What did you expect?
Since map_style_url is not provided - the option to share Location should be hidden/disabled.
Alternatively, admins should be able to hide it within the "settingDefaults" section (e.g. set "UIFeature.shareLocation" to false).
Note that this feature requires registering for getting a key. I'm not sure all HS admins would do that, also some HS might want to disable it because of privacy concerns.

#### What happened instead?
Error message is shown.

### Application version
Element Web 1.10.2