feat: begin implementation of "sub tabs"

src/pages/admin/shell.rs

@@ -15,9 +15,9 @@ pub fn AdminShell() -> impl IntoView {
             <Banner title="R15 Scholarships Admin" logo="/PHS_Stacked_Acronym.png" />
             // We'll put the tabs here.
             <TabSidebarList tabs=vec![
-                TabInfo::new("Home", "/admin/home"),
-                TabInfo::new("Providers", "/admin/providers"),
-                TabInfo::new("Scholarships", "/admin/scholarships"),
+                TabInfo::new("Home", "/admin/home", None),
+                TabInfo::new("Providers", "/admin/providers", None),
+                TabInfo::new("Scholarships", "/admin/scholarships", None),
             ] />
         </AdminLoginContext>
     }