[MNT] [Dependabot](deps): Bump actions/dependency-review-action from …

…3 to 4 (sktime#178)

Bumps
[actions/dependency-review-action](https://github.com/actions/dependency-review-action)
from 3 to 4.

.github/workflows/dependency-review.yml

@@ -17,7 +17,7 @@ jobs:
       - name: 'Checkout Repository'
         uses: actions/checkout@v4
       - name: 'Dependency Review'
-        uses: actions/dependency-review-action@v3
+        uses: actions/dependency-review-action@v4
         with:
           # Possible values: "critical", "high", "moderate", "low"
           # Will fail if a PR introduces a security vulnerability