fix(testing): Fix random failure test (#37887)

Fix the flaky npm package web view test that compared rendered HTML as a
raw string.

Fix
https://github.com/go-gitea/gitea/actions/runs/26524574688/job/78124662707?pr=36564

---------

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Nicolas <bircni@icloud.com>

tests/integration/api_packages_npm_test.go

@@ -304,7 +304,7 @@ func TestPackageNpm(t *testing.T) {
 		resp := MakeRequest(t, req, http.StatusOK)
 		doc := NewHTMLParser(t, resp.Body)
 		rendered, _ := doc.Find(".markup.markdown").Html()
-		assert.Equal(t, `<p dir="auto"><a href="/user2/repo1/src/branch/master/package-subdir/docs/usage.md" rel="nofollow">docs</a>
+		assertHTMLEq(t, `<p dir="auto"><a href="/user2/repo1/src/branch/master/package-subdir/docs/usage.md" rel="nofollow">docs</a>
 <a href="/user2/repo1/src/branch/master/package-subdir/logo.png" rel="nofollow noopener" target="_blank"><img src="/user2/repo1/media/branch/master/package-subdir/logo.png" alt="logo" loading="lazy"/></a></p>
 `, rendered)
 	})

tests/integration/html_helper.go

@@ -5,10 +5,13 @@ package integration
 
 import (
 	"io"
+	"slices"
+	"strings"
 	"testing"
 
 	"github.com/PuerkitoBio/goquery"
 	"github.com/stretchr/testify/assert"
+	"golang.org/x/net/html"
 )
 
 // HTMLDoc struct
@@ -47,3 +50,39 @@ func AssertHTMLElement[T int | bool](t testing.TB, doc *HTMLDoc, selector string
 		assert.Equal(t, v, sel.Length())
 	}
 }
+
+func assertHTMLEq(t testing.TB, expected, actual string) {
+	t.Helper()
+	if expected == actual {
+		return
+	}
+	exp, err := html.Parse(strings.NewReader(expected))
+	if !assert.NoError(t, err) {
+		return
+	}
+	act, err := html.Parse(strings.NewReader(actual))
+	if !assert.NoError(t, err) {
+		return
+	}
+	var normalize func(n *html.Node)
+	normalize = func(n *html.Node) {
+		slices.SortFunc(n.Attr, func(a, b html.Attribute) int {
+			if cmp := strings.Compare(a.Namespace, b.Namespace); cmp != 0 {
+				return cmp
+			}
+			if cmp := strings.Compare(a.Key, b.Key); cmp != 0 {
+				return cmp
+			}
+			return strings.Compare(a.Val, b.Val)
+		})
+		for c := n.FirstChild; c != nil; c = c.NextSibling {
+			normalize(c)
+		}
+	}
+	normalize(exp)
+	normalize(act)
+	var expNormalized, actNormalized strings.Builder
+	assert.NoError(t, html.Render(&expNormalized, exp))
+	assert.NoError(t, html.Render(&actNormalized, act))
+	assert.Equal(t, expNormalized.String(), actNormalized.String())
+}