Resolve "Include a link to the fundraising campain on the contribute page"

What does this MR do?

Changes the link to the TU Delft Covid-19 response fund to the We\Visit crowdfund

Screenshots

before

after

Closes #242 (closed)

Does this MR meet the acceptance criteria?

• I have added tests to validate the new functionality.
• I have updated the documentation accordingly.
• I have added translations for all new client-side text.
• I have updated the changelog accordingly.