feat(ci): add monthly cron for npm audit (#50)

* feat(ci): add monthly cron for npm audit

* fix(ci): remove slack notification

.github/workflows/npm-audit

@@ -0,0 +1,25 @@
+name: NPM Audit
+
+on:
+  schedule:
+    - cron: "0 0 1 * *"
+  workflow_dispatch:
+
+jobs:
+  audit:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: '16'
+      - uses: actions/cache@v2
+        with:
+          path: '**/node_modules'
+          key: ${{ runner.os }}-modules-${{ hashFiles('**/yarn.lock') }}
+          restore-keys: ${{ runner.os }}-
+      - name: Install Dependencies
+        run: yarn
+      - name: Run a security audit
+        run: npx audit-ci --critical --report-type summary