In an evergreen command definition, add_expansions_to_env: true causes all evergreen variables to be added to the environment variables of the subprocess. This is very convenient and a substantial improvement over manually exporting those variables.

However, because the entire evergreen variable set is dropped in, it makes it hard to debug and maintain because it's easy to lose track of which variables are actually needed for which commands. Instead, we should switch uses of it over to include_expansions_in_env, which has the same benefits and avoids the maintenance issue by requiring variables to be explicitly listed.