docs: Include output folder creation

README.md

@@ -364,6 +364,8 @@ The following steps may be used within a GitHub Actions script:
 
 ```yaml
     steps:
+      - name: Create output dirs
+        run: mkdir -p ./test-suite/output/json ./test-suite/conformance/
       - name: Run OpenActive Test Suite
         uses: openactive/openactive-test-suite@master
         with:
@@ -388,7 +390,9 @@ The following steps may be used within a GitHub Actions script:
 
 And as in the parent section, `NODE_CONFIG` must include `"ci": true`.
 
-Note that `outputPath` and `conformanceCertificatePath` must start with `/github/workspace/` to ensure these outputs are accessible in subsequent steps.  
+Note that `outputPath` and `conformanceCertificatePath` must start with `/github/workspace/` to ensure these outputs are accessible in subsequent steps.
+
+Sub-directories must be created before the test suite runs (including a subdirectory of the `output` folder named `json`) e.g. `mkdir -p ./test-suite/output/json ./test-suite/conformance/`.
 
 As in the previous section, `host.docker.internal` must be the host to access your booking system locally to the GitHub action if it is not running in another Docker container. This hostname must also be used within `NODE_CONFIG` for `datasetSiteUrl` and Seller `@id`s.