Make oidc work with respondents auth with guid only

To automatically direct respondents to an external site (which is already authenticated by Catglobe) upon clicking the survey link, bypassing a login prompt, we can proceed as follows:

Input the cgscript on gateway workflow or on the questionnaire dummy:

//Script for gateway
return oidc_site + "authentication/login?respondent=" + User_getQasUser().ResourceGuid + "&respondent_secret=" + QAS_getCurrentQAS().AccessCode;
//Script for dummy
sendToUrl(oidc_site + "authentication/login?respondent=" + User_getQasUser().ResourceGuid + "&respondent_secret=" + QAS_getCurrentQAS().AccessCode);

Then send invitation mail to respondents. When a respondent clicks on survey link in mail, they'll be redirected to external site and automatically logged in.

Here's the flow diagram, to shows how this works