Error 500 when retrieving Project Role Actors

Symptoms

When selecting a project and trying to generate the documentation we are getting a 500 error caused by NullPointerException with this details:

java.lang.NullPointerException
at com.atlassian.jira.bc.projectroles.DefaultProjectRoleService.getProjectRoleActors(DefaultProjectRoleService.java:297) [classes/:?]
at com.atlassian.jira.bc.projectroles.DefaultProjectRoleService.getProjectRoleActors(DefaultProjectRoleService.java:1050) [classes/:?]
at com.eis.jira.plugins.jiradoc.beans.ProjectRepresentation.getProjectRoleMembersRepresentation(ProjectRepresentation.java:224) [?:?]
at com.eis.jira.plugins.jiradoc.beans.ProjectRepresentation.<init>(ProjectRepresentation.java:67) [?:?]
at com.eis.jira.plugins.jiradoc.JiradocServlet.doPost(JiradocServlet.java:156) [?:?]
[...]

Cause

This error was caused due to a bug on Smart Project Config & Documentation versions prior to 3.3.6.

Work-around

Upgrade Smart Project Config & Documentation to version 3.3.6 or higher