Add snapshot test to replace mock coverage

end_to_end_tests/__snapshots__/test_end_to_end.ambr

@@ -1,4 +1,18 @@
 # serializer version: 1
+# name: test_documents_with_errors[bad-status-code]
+  '''
+  Generating /test-documents-with-errors
+  Warning(s) encountered while generating. Client was generated, but some pieces may be missing
+
+  WARNING parsing GET / within default.
+
+  Invalid response status code abcdef (not a valid HTTP status code), response will be omitted from generated client
+
+
+  If you believe this was a mistake or this tool is missing a feature you need, please open an issue at https://github.com/openapi-generators/openapi-python-client/issues/new/choose
+
+  '''
+# ---
 # name: test_documents_with_errors[circular-body-ref]
   '''
   Generating /test-documents-with-errors

end_to_end_tests/documents_with_errors/bad-status-code.yaml

@@ -0,0 +1,14 @@
+openapi: "3.1.0"
+info:
+  title: "There's something wrong with me"
+  version: "0.1.0"
+paths:
+  "/":
+    get:
+      responses:
+        "abcdef":
+          description: "Successful Response"
+          content:
+            "application/json":
+              schema:
+                const: "Why have a fixed response? I dunno"