Rework DocLinkCreator class

[andreaskienle]

Description

DocLinkCreator class should be converted into a hook, e.g. useLink() or useDocumentationLink() or similar which can be used like this (pick one):

• option 1 (the chosen one)

  const { documentationHomepage } = useLink();
  

• option 2

  const link = useLink();
  const documentationHomepage = link(Link.DocumentationHomepage);
  

• option 3

  const link = useLink();
  const documentationHomepage = link('/path/to/homepage');
  

• …

To be implemented:

• remove class from FrontendConfigContext
• replace usages of the class with calls to the hook