Update documentation for questions

[jorg-vr]

I updated the documentation about asking questions on the exercise page.

I also updated the English page to match the dutch page

Related pr: dodona-edu/dodona#4596

[pdawyndt]

Would it be an idea to use the platform announcement feature to address the new features from the latest release for making annotations (reply to annotation, multiline selection, representation of machine annotations, ...), with a reference to the updated documentation page on asking questions?

[bmesuere]

Would it be an idea to use the platform announcement feature to address the new features from the latest release for making annotations (reply to annotation, multiline selection, representation of machine annotations, ...), with a reference to the updated documentation page on asking questions?

No, this is only for urgent messages since they are shown on all pages. There is an open issue to show such info on the home page as part of the next phase of the home page rework.