Show additional alert when opening external tools which are not optimized for mobile devices

[mathebox]

Is your feature request related to a problem? Please describe.
Currently, LTI exercises and peer-assessment are not optimized for mobile devices. Therefore, we show a message in a label to the user right next to the button opening the respective tool. However, this message can be easily overlooked by users.

Describe the solution you'd like
Instead of showing placing a label next to the launch button, we can present a sheet (sliding up from the bottom) upon tapping the launch button. The sheet should contain the original message to the user and a launch confirmation button. The sheet does not need to fill the entire screen.

Affected Component
LTIExerciseHintViewController, PeerAssesmentHintViewController, …

Additional context
Similar to these (but no dependency should be added):

• https://github.com/nathangitter/fluid-interfaces#rewarding-momentum
• https://github.com/huri000/SwiftEntryKit