Fixed empty display name (content.displayname in a room member can be null)
Fixed empty display name (content.displayname in a room member can be null)

rzr/synapse,iot-factory/synapse,TribeMedia/synapse,TribeMedia/synapse,TribeMedia/synapse,howethomas/synapse,matrix-org/synapse,matrix-org/synapse,matrix-org/synapse,iot-factory/synapse,matrix-org/synapse,iot-factory/synapse,illicitonion/synapse,rzr/synapse,rzr/synapse,matrix-org/synapse,rzr/synapse,howethomas/synapse,iot-factory/synapse,illicitonion/synapse,matrix-org/synapse,iot-factory/synapse,illicitonion/synapse,howethomas/synapse,howethomas/synapse,illicitonion/synapse,howethomas/synapse,rzr/synapse,illicitonion/synapse,TribeMedia/synapse,TribeMedia/synapse