The following tests fails on the latest version constantly:

rspec ./spec/mongo/index/view_spec.rb[1:1:1:2:1:1] # Mongo::Index::View#drop_one when provided a session behaves like a failed operation using a session when the operation fails raises an error

rspec ./spec/mongo/operation/drop_index_spec.rb:54 # Mongo::Operation::DropIndex#execute when the index does not exist raises an exception

Since the latest is still in alpha stage, we disable the tests for now, and investigate when a more stable version is available.