Force logout from MAS when logging out from Tchap

[mcalinghee]

• force MAS to disconnect the browser's session when revoking token from Tchap

Illustration :

• login into Tchap by using the MAS (email/pwd or Proconnect)
• check the MAS url

• logout from Tchap
• it will end the browser's session on MAS side, go the MAS URL

[odelcroi]

UX issue :

• after users click on disconnect from MAS screen, they are redirect to MAS login without login_hint.
• when users login again, they are sent to MAS welcome page instead of tchap web