Unable to aquire valid session id using an apex class

From this Article I was able to extract this method here:

First create a VisualForce page with the name: currentUserInfoCtrl and then insert into it:

<apex:page >
 Start_Of_Session_Id{!$Api.Session_ID}End_Of_Session_Id
</apex:page>

Then create a new Apex class that will reference the Apex Page

    @AuraEnabled
    public static String fetchUserSessionId(){
         String sessionId = '';
         // Refer to the Page
         PageReference reportPage = Page.GetSessionIdVF;
         // Get the content of the VF page
         String vfContent = reportPage.getContent().toString();
         System.debug('vfContent '+vfContent);
         // Find the position of Start_Of_Session_Id and End_Of_Session_Id
         Integer startP = vfContent.indexOf('Start_Of_Session_Id') + 'Start_Of_Session_Id'.length(),
         endP = vfContent.indexOf('End_Of_Session_Id');
         // Get the Session Id
         sessionId = vfContent.substring(startP, endP);
         System.debug('sessionId '+sessionId);
         // Return Session Id
         return sessionId;
     }

I was able to get a valid session token using this method, and then attaching this apex class to my Lightning Component.