add govulncheck action

Author: bitfield

.github/workflows/test.yml

@@ -15,3 +15,8 @@ jobs:
           cache: false
       - uses: actions/checkout@v3
       - run: go test ./...
+      - id: govulncheck
+        uses: golang/govulncheck-action@v1
+        with:
+          go-version-input: ${{ matrix.go-version }}
+          go-package: ./...