Update multiversion tests following 4.7.0 branch

See SERVER-31553 for the work done when branching 3.6.This should be done with as part of the upgrade/downgrade project Similar to SERVER-27107, after branching 4.7.0, we should bump the version in the following places:

For master branch:

1. update multiversion to download 4.7.0: https://github.com/mongodb/mongo/blob/r4.7.0-rc0/etc/evergreen.yml#L975
2. update MongoRunner.binVersionSubs
3. bump verify_versions_test.js from 4.7.0 to 4.8.0Dev
4. remove any multiversion tests that are specifically testing 4.4 <~~> 3.new upgrade/downgrade scenarios.