Problem: Dashboard RPM post-install script not sourcing /etc/sysconfig/archivematica-dashboard properly

The export command [here](https://github.com/artefactual-labs/am-packbuild/blob/2092ee13770b6730daf8789473a146d7492f996b/rpm/archivematica/archivematica.spec#L270) does not handle comment lines or quoted variables.