This operation will be performed from the CLI of the system. The below example shows the password being reset to "password"
rdcli system user modify -l admin -la en -p password
This next example demonstrates resetting the password to "Genes!sSL1". Note that the special character "!" needs to be escaped from the shell by a proceeding \
rdcli system user modify -l admin -la en -p Genes\!sSL1
(The above examples both assume a language of English, set by the "-la en" option)