Add index.html suffix

It seems like I need a rewriting function to append this
automatically…? No thanks

Author: backspace

.github/workflows/ci.yaml

@@ -282,7 +282,7 @@ jobs:
 
       - name: Store Playwright report URL
         shell: bash
-        run: echo "PLAYWRIGHT_REPORT_URL=https://boxel-matrix-playwright-reports.stack.cards/${{ steps.timestampid.outputs.timestamp }}/" >> $GITHUB_ENV
+        run: echo "PLAYWRIGHT_REPORT_URL=https://boxel-matrix-playwright-reports.stack.cards/${{ steps.timestampid.outputs.timestamp }}/index.html" >> $GITHUB_ENV
 
       - name: Sleep to wait for Pages deployment
         shell: bash