Add the dependabot post-hook workflow

.github/workflows/dependabot.yml

@@ -0,0 +1,57 @@
+name: Update OTEL Builder Dependencies
+on:
+  push:
+    branches:
+      - dependabot/go_modules/src/otel-collector-builder/**
+  pull_request:
+    branches:
+      - dependabot/go_modules/src/otel-collector-builder/**
+
+jobs:
+  post-hook:
+    # Only proceed if this is a Dependabot‐created PR
+    if: >
+      github.event_name == 'pull_request' &&
+      github.event.pull_request.user.login == 'dependabot[bot]'
+    # Allow the job to approve and merge the PR
+    permissions:
+      contents: write
+      pull-requests: write
+    name: Update the OTEL collector
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-go@v5
+        with:
+          go-version-file: src/otel-collector/go.mod
+
+      - name: Update the OTEL builder version inside the configuration
+        run: |
+          extract_version() {
+            local s="$1"
+            [[ $s =~ ([0-9]+(\.[0-9]+){2})$ ]] && printf '%s\n' "${BASH_REMATCH[1]}"
+          }
+          otel_builder_version=$(extract_version "${{ github.ref_name }}")
+          sed -E -i '' "s#^(\\s*require\\s+go\\.opentelemetry\\.io/collector/cmd/builder\\s+)v?[0-9]+(\\.[0-9]+){2}#\\1v${otel_builder_version}#" src/otel-collector-builder/go.mod
+
+      - name: Build the new OTEL collector version
+        shell: bash
+        run: scripts/regenerate-otel-collector-distribution
+
+      - name: Run the Integrationtest
+        shell: bash
+        run: scripts/subtests/integration-test
+
+      - name: Commit files
+        run: |
+          git config --local user.email "[email protected]"
+          git config --local user.name "dependabot[bot]"
+          git commit -a -m "Adjust the OTEL builder version"
+
+      - name: Push changes
+        uses: ad-m/github-push-action@master
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          branch: ${{ github.head_ref }}
+