server-server api: Fix swapped pdu state update field descriptions
server-server api: Fix swapped pdu state update field descriptions

Signed-off-by: Robert Swain <791ba90935b5b6974c8ea1e530798a6a75db795a@gmail.com>

matrix-org/matrix-doc,matrix-org/matrix-doc,matrix-org/matrix-doc,matrix-org/matrix-doc