The SVN url has been changed by SourceForge. In your repository root, or in an individual module, run the command:
svn switch --relocate https://apertium.svn.sourceforge.net/svnroot/apertium/ https://svn.code.sf.net/p/apertium/svn/

From Apertium

The following pages link to Romance languages:

• User:Youssefsan (← links)
• Apertium-pretransfer (← links)
• Traductions en français (← links)
• Germanic languages (← links)
• Romance language (redirect page) (← links)
  • Spanish (← links)
  • Aromanian (← links)