Attempt 3 at working around R2 brokenness

.github/workflows/build_develop.yml

@@ -26,6 +26,12 @@ jobs:
             R2_URL: ${{ vars.CF_R2_S3_API }}
             R2_PUBLIC_URL: "https://element-web-develop.element.io"
         steps:
+            # Workaround for https://www.cloudflarestatus.com/incidents/t5nrjmpxc1cj
+            - uses: unfor19/install-aws-cli-action@v1
+              with:
+                version: 2.22.35
+                verbose: false
+                arch: amd64
             - uses: actions/checkout@v4
 
             - uses: actions/setup-node@v4
@@ -116,9 +122,6 @@ jobs:
               env:
                   AWS_ACCESS_KEY_ID: ${{ secrets.CF_R2_ACCESS_KEY_ID }}
                   AWS_SECRET_ACCESS_KEY: ${{ secrets.CF_R2_TOKEN }}
-                  # Workaround for https://www.cloudflarestatus.com/incidents/t5nrjmpxc1cj
-                  AWS_REQUEST_CHECKSUM_CALCULATION: WHEN_REQUIRED
-                  AWS_RESPONSE_CHECKSUM_VALIDATION: WHEN_REQUIRED
 
             - name: Deploy to Cloudflare Pages
               id: cfp