tests/integration: simplify code (#37249)

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Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: Claude (Opus 4.7) <noreply@anthropic.com>

tests/integration/api_packages_conda_test.go

@@ -5,7 +5,6 @@ package integration
 
 import (
 	"archive/tar"
-	"archive/zip"
 	"bytes"
 	"fmt"
 	"io"
@@ -16,6 +15,7 @@ import (
 	"code.gitea.io/gitea/models/unittest"
 	user_model "code.gitea.io/gitea/models/user"
 	conda_module "code.gitea.io/gitea/modules/packages/conda"
+	"code.gitea.io/gitea/modules/test"
 	"code.gitea.io/gitea/modules/zstd"
 	"code.gitea.io/gitea/tests"
 
@@ -94,11 +94,9 @@ func TestPackageConda(t *testing.T) {
 			io.Copy(zsw, bytes.NewReader(tarContent))
 			zsw.Close()
 
-			var buf bytes.Buffer
-			zpw := zip.NewWriter(&buf)
-			w, _ := zpw.Create("info-x.tar.zst")
-			w.Write(infoBuf.Bytes())
-			zpw.Close()
+			buf := test.WriteZipArchive(map[string]string{
+				"info-x.tar.zst": infoBuf.String(),
+			})
 
 			fullName := channel + "/" + packageName
 			filename := fmt.Sprintf("%s-%s.conda", packageName, packageVersion)