test: skip Stripe test-clock test when placeholder API key is in use

test_draft_invoices_get_application_fee_amount_applied calls the live
Stripe API (stripe.Account.create, TestClock.create, etc). In CI we
copy settings.yaml.example which ships with
STRIPE_TEST_SECRET_KEY='sk_test_changeme', so the test fails the whole
pytest run with AuthenticationError and blocks PR merges.

Adding a skipif guard on the placeholder key lets CI pass without us
having to store real Stripe secrets in GitHub Actions secrets (which
the maintainer has explicitly opted out of for now). Running the test
locally with a real STRIPE_TEST_SECRET_KEY exported in settings.yaml
still exercises the full path.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: chrisjsimpson

tests/test_draft_invoice_application_fee_applied_time_clock.py

@@ -1,5 +1,6 @@
 import time
 import sys
+import pytest
 import stripe
 from subscribie.settings import settings
 from uuid import uuid4
@@ -8,6 +9,18 @@
 import subprocess
 
 
+_STRIPE_TEST_KEY = settings.get("STRIPE_TEST_SECRET_KEY") or ""
+
+
+@pytest.mark.skipif(
+    not _STRIPE_TEST_KEY or "changeme" in _STRIPE_TEST_KEY,
+    reason=(
+        "Requires a real STRIPE_TEST_SECRET_KEY. The placeholder "
+        "'sk_test_changeme' from settings.yaml.example is in use, so this "
+        "test would call the live Stripe API and 401. Run locally with a "
+        "real key to exercise the Stripe test-clock path."
+    ),
+)
 def test_draft_invoices_get_application_fee_amount_applied():
     """
     Verify that future draft invoices generated by existing (and active)