Do not use threads at all for upgrade_postgres_extension #2049
Do not use threads at all for upgrade_postgres_extension #2049

dbirchak/cartodb,raquel-ucl/cartodb,nyimbi/cartodb,thorncp/cartodb,thorncp/cartodb,CartoDB/cartodb,DigitalCoder/cartodb,thorncp/cartodb,raquel-ucl/cartodb,codeandtheory/cartodb,nuxcode/cartodb,dbirchak/cartodb,DigitalCoder/cartodb,UCL-ShippingGroup/cartodb-1,nuxcode/cartodb,codeandtheory/cartodb,CartoDB/cartodb,thorncp/cartodb,CartoDB/cartodb,UCL-ShippingGroup/cartodb-1,DigitalCoder/cartodb,bloomberg/cartodb,dbirchak/cartodb,thorncp/cartodb,bloomberg/cartodb,bloomberg/cartodb,nuxcode/cartodb,codeandtheory/cartodb,bloomberg/cartodb,codeandtheory/cartodb,DigitalCoder/cartodb,nyimbi/cartodb,future-analytics/cartodb,splashblot/dronedb,dbirchak/cartodb,splashblot/dronedb,nuxcode/cartodb,CartoDB/cartodb,nyimbi/cartodb,splashblot/dronedb,dbirchak/cartodb,raquel-ucl/cartodb,splashblot/dronedb,raquel-ucl/cartodb,bloomberg/cartodb,raquel-ucl/cartodb,UCL-ShippingGroup/cartodb-1,nyimbi/cartodb,splashblot/dronedb,CartoDB/cartodb,future-analytics/cartodb,future-analytics/cartodb,future-analytics/cartodb,future-analytics/cartodb,DigitalCoder/cartodb,UCL-ShippingGroup/cartodb-1,codeandtheory/cartodb,nuxcode/cartodb,UCL-ShippingGroup/cartodb-1,nyimbi/cartodb