remove default value from last_modified property
remove default value from last_modified property

puttarajubr/commcare-hq,qedsoftware/commcare-hq,dimagi/commcare-hq,qedsoftware/commcare-hq,puttarajubr/commcare-hq,dimagi/commcare-hq,qedsoftware/commcare-hq,qedsoftware/commcare-hq,puttarajubr/commcare-hq,qedsoftware/commcare-hq,puttarajubr/commcare-hq,dimagi/commcare-hq,dimagi/commcare-hq,dimagi/commcare-hq