chore: boxes tests cause resource issues (#10676)

this forces them to run in serial

.github/workflows/ci.yml

@@ -868,11 +868,26 @@ jobs:
           alert-comment-cc-users: "@ludamad @codygunton"
           max-items-in-chart: 50
 
-  boxes-test:
+  boxes:
     needs: [e2e-test-gate, configure]
     runs-on: ${{ needs.configure.outputs.username }}-x86
+    steps:
+      - uses: actions/checkout@v4
+        with: { ref: "${{ github.event.pull_request.head.sha }}" }
+      - uses: ./.github/ci-setup-action
+        with:
+          concurrency_key: boxes-${{ matrix.box }}-${{ matrix.browser }}
+      - name: Build
+        working-directory: ./boxes
+        timeout-minutes: 40
+        run: earthly-ci +export-boxes
+
+  boxes-test:
+    needs: [boxes, configure]
+    runs-on: ${{ needs.configure.outputs.username }}-x86
     strategy:
       fail-fast: false
+      max-parallel: 1
       matrix:
         box: [vanilla, react]
         # intermittent issues with firefox https://github.com/AztecProtocol/aztec-packages/issues/6676
@@ -884,10 +899,6 @@ jobs:
       - uses: ./.github/ci-setup-action
         with:
           concurrency_key: boxes-${{ matrix.box }}-${{ matrix.browser }}
-      - name: Build
-        working-directory: ./boxes
-        timeout-minutes: 40
-        run: earthly-ci +export-boxes
       - name: Box test
         working-directory: ./boxes
         timeout-minutes: 40