Bump django from 1.11.14 to 1.11.15 in /arches/install
Bump django from 1.11.14 to 1.11.15 in /arches/install

Bumps [django](https://www.djangoproject.com/) from 1.11.14 to 1.11.15.

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
archesproject/arches,archesproject/arches,archesproject/arches,archesproject/arches