MongoDB Ruby projects are not using modern RSpec .expect syntax (they are using old .should syntax.) This is causing code reviews to be delayed due to nits about expect vs. should.
 
Let's fix the issue permanently in all projects. I've used Transpec gem to do the port, it seems to be working with issue.
 
Please merge the following PRs:
 

• https://github.com/mongodb/mongoid/pull/5553
• https://github.com/mongodb/mongo-ruby-driver/pull/2694
• https://github.com/mongodb/bson-ruby/pull/302

These PRs only change test files, and so should be considered "safe" to merge. I appreciate an expedited review as these will have conflicts with other PRs.