Re-enable test_delayed_repo_init

Porting this test needed some fundamental help because we haven't had
any tests that required changing the tenant config before.

Change-Id: Ife0bf391340d24f33b516afdb24626415ad7d65f
Story: 2001134
Task: 4847
diff --git a/tests/fixtures/tenants/delayed-repo-init.yaml b/tests/fixtures/tenants/delayed-repo-init.yaml
new file mode 100644
index 0000000..433e6f7
--- /dev/null
+++ b/tests/fixtures/tenants/delayed-repo-init.yaml
@@ -0,0 +1,11 @@
+- tenant:
+    name: tenant-one
+    source:
+      gerrit:
+        config-projects:
+          - common-config
+        untrusted-projects:
+          - org/project
+          - org/project1
+          - org/project2
+          - org/new-project