[chore] Add OCB release test workflow (open-telemetry#12573)

<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->
#### Description
This PR adds a workflow that tests if the builder can be released with
the current source code and release setup.
It takes the source code from this repo and adds the release config and
Dockerfile from the collector-releases repo, then it runs a test
release.

Tested on my fork:
https://github.com/mowies/opentelemetry-collector/actions/runs/13761002306/job/38476925222
(pipeline fails because of goreleaser pro features still being enabled,
but the rest works)

<!-- Issue number if applicable -->
#### Link to tracking issue
Fixes open-telemetry#12570

---------

Signed-off-by: Moritz Wiesinger <[email protected]>
Co-authored-by: Douglas Camata <[email protected]>

Author: mowies

.github/workflows/builder-snapshot.yaml

@@ -0,0 +1,90 @@
+name: Builder - Snapshot build
+on:
+  push:
+    branches: [main]
+
+  # on PRs touching the builder
+  pull_request:
+    branches: [main]
+    paths:
+      - "cmd/builder"
+
+env:
+  # renovate: datasource=github-tags depName=goreleaser-pro packageName=goreleaser/goreleaser-pro
+  GORELEASER_PRO_VERSION: v2.7.0
+
+jobs:
+  snapshot:
+    runs-on: ubuntu-24.04
+    if: ${{ github.repository_owner == 'open-telemetry' }}
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: .core
+
+      - name: Pull the latest releases repo
+        uses: actions/checkout@v4
+        with:
+          path: opentelemetry-collector-releases
+          repository: open-telemetry/opentelemetry-collector-releases
+
+      - name: Copy release files
+        run: cp -R ./opentelemetry-collector-releases/cmd/builder/. ./.core/cmd/builder/
+
+      - uses: sigstore/cosign-installer@d7d6bc7722e3daa8354c50bcb52f4837da5e9b6a # v3.8.1
+      - uses: anchore/sbom-action/download-syft@f325610c9f50a54015d37c8d16cb3b0e2c8f4de0 # v0.18.0
+
+      - uses: docker/setup-qemu-action@29109295f81e9208d7d86ff1c6c12d2833863392 # v3.6.0
+        with:
+          platforms: amd64, arm64,ppc64le
+
+      - uses: docker/setup-buildx-action@b5ca514318bd6ebac0fb2aedd5d36ec1b5c232a2 # v3.10.0
+
+      - name: Setup Go
+        uses: actions/setup-go@f111f3307d8850f501ac008e886eec1fd1932a34 # v5.3.0
+        with:
+          go-version: "~1.24"
+
+      - name: Check GoReleaser
+        uses: goreleaser/goreleaser-action@90a3faa9d0182683851fbfa97ca1a2cb983bfca3 # v6.2.1
+        with:
+          distribution: goreleaser-pro
+          version: ${{ env.GORELEASER_PRO_VERSION }}
+          args: check --verbose -f .core/cmd/builder/.goreleaser.yml
+        env:
+          GORELEASER_KEY: ${{ secrets.GORELEASER_KEY }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Run GoReleaser
+        uses: goreleaser/goreleaser-action@90a3faa9d0182683851fbfa97ca1a2cb983bfca3 # v6.2.1
+        with:
+          distribution: goreleaser-pro
+          version: ${{ env.GORELEASER_PRO_VERSION }}
+          args: --snapshot --clean -f .core/cmd/builder/.goreleaser.yml
+        env:
+          GORELEASER_KEY: ${{ secrets.GORELEASER_KEY }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          COSIGN_YES: false
+          SKIP_SIGNS: true
+
+        # Only create an issue if the workflows fails on push to main branch
+      - name: File an issue if the workflow failed
+        if: failure() && github.ref == 'refs/heads/main'
+        run: |
+          template=$(cat <<'END'
+          [Link to job log](%s)
+
+          <details>
+          <summary>Last 100 lines of log</summary>
+
+          ```
+          %s
+          ```
+          </details>
+          END
+          )
+          job_url="$(gh run view ${{ github.run_id }} -R ${{ github.repository }} --json jobs -q '.jobs[] | select(.name == "snapshot") | .url')"
+          body="$(printf "$template" "$job_url" "$(tail -n100 log.out | tail -c63K)")"
+          gh issue create -R ${{ github.repository }} -t 'OCB snapshot workflow failed' -b "$body" -l 'ci-cd' -l 'area:builder'
+        env:
+          GH_TOKEN: ${{ github.token }}