Merge pull request #47 from cyber-dojo/set-fetch-depth

CI: set fetch-depth to 2 since we needs previous commit sha for caching

.github/workflows/main.yml

@@ -34,7 +34,7 @@ jobs:
     steps:
       - uses: actions/[email protected]
         with:
-          fetch-depth: 1
+          fetch-depth: 2
 
       - name: Prepare outputs for workflow jobs
         id: vars