Update "Restricted access" section to say Admin (#5960)

Swapping "Team Admin" with "Admin" b/c "Team Admin" concept hasn't been introduced yet.

Author: lizokm

src/docs/product/accounts/membership.mdx

@@ -69,7 +69,7 @@ Open membership is enabled by default, which allows members to join, leave, and
 - Access to a Project is limited to the Team that owns the project. However, with open membership,
   members can join and add members to teams.
 - To further restrict access to a Project, you can control access to Teams by making them accessible
-  only through invitation by a Manager, Owner, or Team Admin.
+  only through invitation by a Manager, Owner, or Admin.
 
 To restrict Team access, go to Organization Settings and flip the “Open Membership” toggle.