changed to RSpec's expect syntax

I decided to change clearance to expect syntax for a project I was working on.  If, you want what I did, great!  If, not, you can just close this.

Please note, I have not done a poll request before.  If I have done it incorrectly, I apologize.
If the line still needs to be broken up, then do so like:

```ruby
constraint_matches = signed_out_constraint.matches?(
  request_without_remember_token
)
```

Each argument gets its own line. Closing parent on its own line. Do not indent the arguments. This is our prefered style of breaking up argument lists.