Add required envvar for dev environment

.env.dev

@@ -12,6 +12,7 @@ MUSIC_DIRECTORY_PATH=/music
 BROWSABLE_API_ENABLED=True
 FORWARDED_PROTO=http
 LDAP_ENABLED=False
+FUNKWHALE_SPA_HTML_ROOT=http://nginx/front/
 
 # Uncomment this if you're using traefik/https
 # FORCE_HTTPS_URLS=True

changes/changelog.d/envvar-spa-root.bugfix

+Add required envvar for dev environment (!668)