Have permissions decorators check user signed in

Rather than force us to write the decorators in a specific order let’s
just have one decorator call the other. This should make fewer lines of
code, and fewer annoying test failures. It also means that the same way
of raising a `401` (through the `current_app` method) is used
everywhere.

app/main/views/index.py

@@ -6,7 +6,7 @@ from flask import (
     request,
     url_for,
 )
-from flask_login import current_user, login_required
+from flask_login import current_user
 from notifications_utils.international_billing_rates import (
     INTERNATIONAL_BILLING_RATES,
 )
@@ -17,7 +17,7 @@ from app.main import main
 from app.main.forms import FieldWithNoneOption, SearchByNameForm
 from app.main.views.feedback import QUESTION_TICKET_TYPE
 from app.main.views.sub_navigation_dictionaries import features_nav, pricing_nav
-from app.utils import get_logo_cdn_domain
+from app.utils import get_logo_cdn_domain, user_is_logged_in
 
 
 @main.route('/')
@@ -51,7 +51,7 @@ def error(status_code):
 
 
 @main.route("/verify-mobile")
-@login_required
+@user_is_logged_in
 def verify_mobile():
     return render_template('views/verify-mobile.html')