ci: bump dependabot/fetch-metadata to v3

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: jakub-k-slys

.github/workflows/auto-approve-dependabot.yaml

@@ -19,7 +19,7 @@ jobs:
                   private-key: ${{ secrets.APP_PRIVATE_KEY }}
             - name: Dependabot metadata
               id: metadata
-              uses: dependabot/fetch-metadata@v2
+              uses: dependabot/fetch-metadata@v3
               with:
                   github-token: ${{ secrets.GITHUB_TOKEN }}
             - name: Approve a PR
@@ -43,7 +43,7 @@ jobs:
                   private-key: ${{ secrets.APP_PRIVATE_KEY }}
             - name: Dependabot metadata
               id: metadata
-              uses: dependabot/fetch-metadata@v2
+              uses: dependabot/fetch-metadata@v3
               with:
                   github-token: ${{ secrets.GITHUB_TOKEN }}
             - name: Enable auto-merge for Dependabot PRs