Necessary for the usage of the URL Mapping Editor from the App Links
Assistent.

Currently, custom tabs don't work with the current SkIDentity workflow
because of security reasons (missing user interaction and redirects
within the custom tab), see:

- https://github.com/openid/AppAuth-Android/issues/353#issuecomment-399799189
- https://stackoverflow.com/a/70026598
- https://authguidance.com/basicandroidapp-execution/ (Step 9)

A solution would be to adjust SkIDentity. There has to be a static
website that triggers a user interaction and than redirects to the
scheme registered within the intent-filter.

"Declaration of a project's namespace using the package attribute of the
Android manifest is deprecated in favour of a namespace declaration in
build files."