Remove unused states (#8345)

These state files were snapshots of the Redux state used for
integration tests that have since been removed. Only three of these
states were still used - the three that correspond with the remaining
integration tests.

The default state used when the test environment is spun up was changed
to be the first of these three (`confirm sig requests`) so that the old
default state could safely be removed as well.

Author: Gudahtt

development/mock-dev.js

@@ -42,7 +42,7 @@ if (routerPath) {
   queryString = qs.parse(routerPath.split('?')[1])
 }
 
-selectedView = queryString.view || 'send new ui'
+selectedView = queryString.view || 'confirm sig requests'
 const firstState = states[selectedView]
 updateQueryParams(selectedView)