Adjustments and additions to the test suite

[meg-gutshall]

Description

• I created a generators.rb file in config/initializers that would use RSpec as the default test framework whenever I run a generator as well as skip assets and helper files.
• I added the CEP favicon image.
• I added a few more Devise configs.
• I changed the traits in the User factory to be nested factories. This way, we can call build(:admin) or create(:volunteer) instead of build(:user, :admin) or create(:user, :volunteer). It makes more sense to use traits for other attributes that won't affect the workflow of the user.
• I created a sessions#new spec to test the changes I made to the testing configs.

[meg-gutshall]

The two failing specs are because Chromedriver isn't starting up in the test suite. I was having this issue locally and then I installed it with the command brew install --cask chromedriver. Then I had to cd into the directory of the version I had just installed and mark it as safe to use with xattr -d com.apple.quarantine chromedriver and it worked from there.

[garettarrowood]

I'll get the lint and tests passing again on main. Thank you for these great additions!