Stamp no commit in this repository's own image recipes either (hq issue 363, review of #292)

The genesis image copies the whole clone with .git, so its controller
carried the commit it was built at, as the bundles did.

internal/builder/reproducible_test.go

@@ -106,3 +106,40 @@ func TestTheGoToolchainStampsNoVersionControl(t *testing.T) {
 		t.Fatalf("the go toolchain stamps the commit into what it compiles: %q", joined)
 	}
 }
+
+// **And so does every recipe in this repository that compiles Go** (review of issue 363's fix): the
+// controller's genesis image copies the whole clone, `.git` with it, and the reference images beside it
+// are built the same way by the Makefile.
+func TestEveryGoRecipeInThisRepositoryStampsNoVersionControl(t *testing.T) {
+	root := filepath.Join("..", "..")
+	var recipes []string
+	err := filepath.WalkDir(root, func(path string, d os.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if d.IsDir() && (d.Name() == "vendor" || d.Name() == "testdata" || d.Name() == ".git") {
+			return filepath.SkipDir
+		}
+		if !d.IsDir() && d.Name() == "Dockerfile" {
+			recipes = append(recipes, path)
+		}
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(recipes) == 0 {
+		t.Fatal("no recipe found in this repository")
+	}
+	for _, path := range recipes {
+		body, err := os.ReadFile(path)
+		if err != nil {
+			t.Fatal(err)
+		}
+		for _, line := range strings.Split(string(body), "\n") {
+			if strings.Contains(line, "go build") && !strings.Contains(line, "-buildvcs=false") {
+				t.Errorf("%s compiles Go and stamps the commit into it: %s", path, strings.TrimSpace(line))
+			}
+		}
+	}
+}