Remove old API key and service ID combo

Once all our users have upgraded to the latest clients they won’t need
this. The latest clients only use the combined key and service ID.

Discuss: when can we safely remove it?

app/templates/views/api/keys/show.html

@@ -32,17 +32,4 @@
 
     </div>
 
-    <h2 class='heading-medium'>For older API clients</h2>
-
-    <p>
-      If the client you’re using needs a service ID and an API key,
-      use these values:
-    </p>
-
-    <div class="bottom-gutter">
-      {{ api_key(service_id, 'Service ID', thing='service ID') }}
-    </div>
-
-    {{ api_key(secret, 'API key') }}
-
 {% endblock %}

tests/app/main/views/test_api_integration.py

@@ -248,7 +248,7 @@ def test_should_show_create_api_key_page(
 
 
 def test_should_create_api_key_with_type_normal(
-    logged_in_client,
+    client_request,
     api_user_active,
     mock_login,
     mock_get_api_keys,
@@ -258,27 +258,22 @@ def test_should_create_api_key_with_type_normal(
     mocker,
 ):
     post = mocker.patch('app.notify_client.api_key_api_client.ApiKeyApiClient.post', return_value={'data': fake_uuid})
-    service_id = str(uuid.uuid4())
 
-    response = logged_in_client.post(
-        url_for('main.create_api_key', service_id=service_id),
-        data={
+    page = client_request.post(
+        'main.create_api_key',
+        service_id=SERVICE_ONE_ID,
+        _data={
             'key_name': 'Some default key name 1/2',
             'key_type': 'normal'
-        }
+        },
+        _expected_status=200,
     )
 
-    assert response.status_code == 200
-    page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')
-    keys = page.find_all('span', {'class': 'api-key-key'})
-    for index, key in enumerate([
-        'some_default_key_name_12-{}-{}'.format(service_id, fake_uuid),
-        service_id,
-        fake_uuid
-    ]):
-        assert keys[index].text.strip() == key
+    assert page.select_one('span.api-key-key').text.strip() == (
+        'some_default_key_name_12-{}-{}'.format(SERVICE_ONE_ID, fake_uuid)
+    )
 
-    post.assert_called_once_with(url='/service/{}/api-key'.format(service_id), data={
+    post.assert_called_once_with(url='/service/{}/api-key'.format(SERVICE_ONE_ID), data={
         'name': 'Some default key name 1/2',
         'key_type': 'normal',
         'created_by': api_user_active.id