Previously, we indicated enterprise build variants by including module: enterprise for each variant in our evergreen.yml. However, this option became unavailable after merging the mongo-enterprise-module into the mongo repository. Currently, we use --enableEnterpriseTests, but this approach lacks clarity. We're considering Create new expansion clearly identify community or enterprise build variants

Per this thread (https://mongodb.slack.com/archives/C05V4F6GZ6J/p1712256330811279 ), we have (tentative!) consensus within the team to add an explicit variable (via "expansions") to indicate community/enterprise status.

Note: I (Steve) would also like to see lint-enforcement for this setting.