Introduce retry mechanism for npm install in CI/CD

This commit addresses occasional pipeline failures caused by transient
network errors during dependency installation with `npm ci`. It
centralizes the logic for installing npm dependencies and introduces a
retry mechanism.

The new approach will attempt `npm ci` up to 5 times with a 5-second
interval between each attempt, thereby increasing the resilience of
CI/CD pipelines.

This commit adds a new script `npm-install.js` with `npm run
install-deps` command to centralize npm dependency installation process
throughout the project. Separate testing of scripts to a separate
workflow.

It removes unused `install` dependency from `package.json`.

.github/workflows/checks.external-urls.yaml

@@ -8,11 +8,15 @@ jobs:
   run-check:
     runs-on: ubuntu-latest
     steps:
-      - name: Checkout
+      -
+        name: Checkout
         uses: actions/checkout@v2
-      - name: Setup node
+      -
+        name: Setup node
         uses: ./.github/actions/setup-node
-      - name: Install dependencies
-        run: npm ci
-      - name: Test
+      -
+        name: Install dependencies
+        uses: ./.github/actions/npm-install-dependencies
+      -
+        name: Test
         run: npm run check:external-urls