Fix wrong domain in app.json
Fix wrong domain in app.json

Signed-off-by: Sheogorath <1c2647ce2ee8a4ec8e5c8b1b245ca38f94844bab@shivering-isles.com>

hackmdio/hackmd,hackmdio/hackmd,jackycute/HackMD,hackmdio/hackmd,jackycute/HackMD,jackycute/HackMD