refactor: use shared ProfileUpdate validation in admin routes

tests/test_admin/test_admin_routes.py

@@ -153,7 +153,7 @@ async def test_update_profile(client: AsyncClient) -> None:
             "family_name": "Smith",
             "preferred_username": "bobby",
             "email": "bob@example.com",
-            "phone_number": "+1234567890",
+            "phone_number": "+46701234567",
             "picture": "https://example.com/bob.jpg",
             "locale": "en-US",
         },
@@ -183,7 +183,23 @@ async def test_update_profile_invalid_email(client: AsyncClient) -> None:
         headers={"X-CSRF-Token": token},
     )
     assert response.status_code == 200
-    assert "Invalid email" in response.text
+    assert "alert" in response.text
+    assert "email" in response.text.lower()
+
+
+@pytest.mark.asyncio
+async def test_update_profile_invalid_phone(client: AsyncClient) -> None:
+    await _login(client)
+    target = await _create_target_user(client, username="bob")
+    token = await get_csrf_token(client)
+    response = await client.post(
+        f"/admin/users/{target.userid}/profile",
+        data={"phone_number": "not-a-phone"},
+        headers={"X-CSRF-Token": token},
+    )
+    assert response.status_code == 200
+    assert "alert" in response.text
+    assert "phone" in response.text.lower()
 
 
 @pytest.mark.asyncio