Previously, the embargo tests were running expensive setup once for
test example. This change refactors the setup to only run once per
test group. Overall, this results in over 50% faster testing time.
**BEFORE**
```
% bundle exec rspec ./spec/system/embargo_show_spec.rb
Run options: exclude {:smoke_test=>true}
Randomized with seed 38550
.....
Top 5 slowest examples (396.2 seconds, 100.0% of total time):
Display an ETD with embargoed content viewed by depositor pre-graduation
93.76 seconds ./spec/system/embargo_show_spec.rb:62
Display an ETD with embargoed content viewed by unauthenticated user post-graduation
89.25 seconds ./spec/system/embargo_show_spec.rb:138
Display an ETD with embargoed content viewed by approver with Versions enabled
84.82 seconds ./spec/system/embargo_show_spec.rb:109
Display an ETD with embargoed content viewed by a school approver post-graduation
64.39 seconds ./spec/system/embargo_show_spec.rb:121
Display an ETD with embargoed content viewed by approver pre-graduation
63.98 seconds ./spec/system/embargo_show_spec.rb:87
Finished in 6 minutes 36 seconds (files took 15.28 seconds to load)
5 examples, 0 failures
Randomized with seed 38550
```
**AFTER**
```
% bundle exec rspec ./spec/system/embargo_show_spec.rb --seed 38550
Run options: exclude {:smoke_test=>true}
Randomized with seed 38550
.....
Top 5 slowest examples (72.11 seconds, 54.1% of total time):
Display an ETD with embargoed content post graduation
22.21 seconds ./spec/system/embargo_show_spec.rb:112
Display an ETD with embargoed content viewed by approver pre-graduation
15.97 seconds ./spec/system/embargo_show_spec.rb:83
Display an ETD with embargoed content viewed by depositor pre-graduation
13.81 seconds ./spec/system/embargo_show_spec.rb:61
Display an ETD with embargoed content base etd has expected embargo values after creation
10.12 seconds ./spec/system/embargo_show_spec.rb:47
Display an ETD with embargoed content viewed by approver with Versions enabled
10 seconds ./spec/system/embargo_show_spec.rb:102
Finished in 2 minutes 13.3 seconds (files took 15.44 seconds to load)
5 examples, 0 failures
Randomized with seed 38550
```