In repl_set_config.idl the configTerm field has a max value of int max but is derived from the term field of the original primary. If the term that is used here were to ever be above int::max and below int64::max that would cause a parsing crash. configTerm should be parsed as a long long like other uses of term in the code.

This also requires changes to repl_set_heartbeat_response.h/cpp since we store the configTerm as an int in that class, heartbeats won't establish without appropriate changes there.