Test default extensions view

Author: Joel Collins

tests/test_server_default_views.py

@@ -2,3 +2,8 @@ def test_docs(thing, thing_client, app_ctx):
     with thing_client as c:
         assert c.get("/docs/swagger").json == thing.spec.to_dict()
         assert c.get("/docs/swagger-ui").status_code == 200
+
+
+def test_extensions(thing, thing_client, app_ctx):
+    with thing_client as c:
+        assert c.get("/extensions").json == []