chore: add GHA to test card ui builds (#2333)

ensures that build tooling for cards UI is functional. This is mainly
for verifying dependabot upgrades, which can introduce version conflicts
in the build.

Note: Had to dismiss two CodeQL warnings as false-positives, most likely
due to line number changes from earlier dismissed warnings in `main.js`

.github/workflows/test-card-build.yml

@@ -0,0 +1,23 @@
+name: Test Card UI builds
+
+on:
+  pull_request:
+    branches:
+      - master
+    paths:
+      - 'metaflow/plugins/cards/ui/**'
+
+jobs:
+  testbuild:
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: ./metaflow/plugins/cards/ui
+    steps:
+      - uses: actions/checkout@v4
+      - name: Use Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20.x'
+      - run: npm ci
+      - run: npm run build