Rename fixtures directory to job_fixtures to prepare for adding view_fixtures
directory in the following commits.
Change-Id: Ic20997cae020b542ddc22bf444fa6b92fbcae064
As Jinja2 provides functionality other than interpolation, it's entirely
feasible to use it outside of a context where there are template
variables. This change ensures that we always deep format Jinja2
templates, even when we wouldn't normally interpolate a regular JJB
template.
Change-Id: Ia3f86dd2073d48594eaf791fa2277db7e5ebf0ab