fix: prevent panic when GitLab release has more links than sources (#36295) (#36305)

Backport #36295 by argoyle

Fixes #36292

Co-authored-by: Joakim Olsson <joakim@unbound.se>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

modules/migration/release.go

@@ -10,9 +10,12 @@ import (
 
 // ReleaseAsset represents a release asset
 type ReleaseAsset struct {
-	ID            int64
-	Name          string
-	ContentType   *string `yaml:"content_type"`
+	ID   int64
+	Name string
+
+	// There was a field "ContentType (content_type)" because Some forges can provide that for assets,
+	// but we don't need it when migrating, so the field is omitted here.
+
 	Size          *int
 	DownloadCount *int `yaml:"download_count"`
 	Created       time.Time

services/migrations/github.go

@@ -329,7 +329,6 @@ func (g *GithubDownloaderV3) convertGithubRelease(ctx context.Context, rel *gith
 		r.Assets = append(r.Assets, &base.ReleaseAsset{
 			ID:            asset.GetID(),
 			Name:          asset.GetName(),
-			ContentType:   asset.ContentType,
 			Size:          asset.Size,
 			DownloadCount: asset.DownloadCount,
 			Created:       asset.CreatedAt.Time,

services/migrations/gitlab.go

@@ -316,12 +316,11 @@ func (g *GitlabDownloader) convertGitlabRelease(ctx context.Context, rel *gitlab
 
 	httpClient := NewMigrationHTTPClient()
 
-	for k, asset := range rel.Assets.Links {
+	for _, asset := range rel.Assets.Links {
 		assetID := asset.ID // Don't optimize this, for closure we need a local variable
 		r.Assets = append(r.Assets, &base.ReleaseAsset{
 			ID:            int64(asset.ID),
 			Name:          asset.Name,
-			ContentType:   &rel.Assets.Sources[k].Format,
 			Size:          &zero,
 			DownloadCount: &zero,
 			DownloadFunc: func() (io.ReadCloser, error) {

services/migrations/main_test.go

@@ -171,7 +171,6 @@ func assertReactionsEqual(t *testing.T, expected, actual []*base.Reaction) {
 func assertReleaseAssetEqual(t *testing.T, expected, actual *base.ReleaseAsset) {
 	assert.Equal(t, expected.ID, actual.ID)
 	assert.Equal(t, expected.Name, actual.Name)
-	assert.Equal(t, expected.ContentType, actual.ContentType)
 	assert.Equal(t, expected.Size, actual.Size)
 	assert.Equal(t, expected.DownloadCount, actual.DownloadCount)
 	assertTimeEqual(t, expected.Created, actual.Created)