GZL-4963|Update of the administration guide of TM to add a note about organization management scope

Test-Management/admin.md

@@ -445,6 +445,9 @@ The admin is able to view the user preferences, regarding gazelle use, which are
 
 The administrator has the possibility to edit Administrations registered into gazelle, or to add new organization/companies.
 
+**The information related to each organization of this page are scoped to the selected testing session. 
+  They can be different if the testing session changes.**
+
 To do so, the admin shall go to menu Administration → Manage → Manage Organizations.
 
 ![](./media/manage_organization.png)