Smoke test binaries for EL7 compatiblity

This adds a quick smoke test of our binaries to verify we haven't exceeeded the
maximum GLIBC (2.17) version during linking which would break our ability to
execute on EL7 machines.

.github/workflows/build.yml

@@ -5,6 +5,7 @@ on:
     branches:
       - main
       - release/**
+      - releng/**
   workflow_dispatch:
     inputs:
       build-ref:
@@ -281,6 +282,44 @@ jobs:
           name: ${{ env.PKG_NAME }}_${{ needs.get-product-version.outputs.product-version }}_${{ matrix.goos }}_${{ matrix.goarch }}.zip
           path: ${{ env.PKG_NAME }}_${{ needs.get-product-version.outputs.product-version }}_${{ matrix.goos }}_${{ matrix.goarch }}.zip
 
+  minimum-os:
+    name: OS Compatibility
+    # A quick smoke test of our binaries on our minimum target OS (RHEL 7). Why RHEL 7? Because the glibc version is that old (2.17).
+    needs:
+      - get-go-version
+      - get-product-version
+      - build-linux
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      # Note: Ideally we'd test all our target archs, unfortunately availability of containers of these OS's vary.
+      # For instance there is no ubi7 image for arm64 (there is on ubi8), RHBZ#1728771. And none at all for arm.
+      # So we have to settle for only being able to validate where we can, which is just amd64.
+      matrix:
+        goos: [linux]
+        goarch: ["amd64"]
+    steps:
+      - uses: actions/setup-go@4d34df0c2316fe8122ab82dc22947d607c0c91f9 # v4.0.0
+        with:
+          go-version: ${{needs.get-go-version.outputs.go-version}}
+      - uses: actions/download-artifact@9bc31d5ccc31df68ecc42ccf4149144866c47d8a # v3.0.2
+        with:
+          name: ${{ env.PKG_NAME }}_${{ needs.get-product-version.outputs.product-version }}_${{ matrix.goos }}_${{ matrix.goarch }}.zip
+      - name: Test binary
+        env:
+          artifact_name: ${{ env.PKG_NAME }}_${{ needs.get-product-version.outputs.product-version }}_${{ matrix.goos }}_${{ matrix.goarch }}.zip
+        run: |
+          echo "::group::Unpack and Prep"
+          docker pull "${{matrix.image}}"
+          unzip "$artifact_name"
+          echo "::group::Diagnostics"
+          echo "CGO related build information:"
+          go version -m ./nomad | grep CGO
+          echo "GLIBC links:"
+          go tool nm ./nomad | grep -i glibc | cut -d @ -f 2-3 | sort --version-sort | uniq
+          echo "::group::Smoke test binary"
+          docker run --rm -v "$PWD:/src" registry.access.redhat.com/ubi7/ubi-minimal:7.9-1057 /src/nomad version
+
 permissions:
   contents: read
 # This placed here for when the Nomad team is ready to build docker images.