[TC-642] modify template (#3)

https://eva.avroid.tech/desk/Task/TC-642#be-dorabotat-shablon-servisov-backend

Дорабатываем шаблон сервисов по требованиям: https://eva.avroid.tech/project/Document/DOC-002710#trebovanija-k-versijam

Reviewed-on: https://git.avroid.tech/Templates/template-backend-service/pulls/3
Reviewed-by: Victor Stratov <victor.stratov@avroid.team>
Reviewed-by: Petr Brovchenko <petr.brovchenko@avroid.team>
Co-authored-by: Nadezhda <nadezhda.lavrentieva@avroid.team>
Co-committed-by: Nadezhda <nadezhda.lavrentieva@avroid.team>

tests/samples.py

@@ -1,9 +1,7 @@
 ACCOUNT_1 = {
-    "country_id": 1,
-    "iso_3166_code_alpha3": "RU",
+    "id": 1,
 }
 
 ACCOUNT_2 = {
-    "country_id": 2,
-    "iso_3166_code_alpha3": "EN",
+    "id": 2,
 }