fix(github_graphql): stop requesting unused descriptionHTML for releases (#9248)

The release extractor fills github_releases.description_html from
description and never reads descriptionHTML, but the collector still
asks GitHub for it. Rendering release notes to HTML for a full page of
100 releases can exceed GitHub's GraphQL time limit on repositories with
long release notes: the API returns 502/504, the three retries hit the
same limit, and Collect Releases fails with "pageInfo is nil".

On a repository with 86 releases and ~437 KB of release notes, the
current query returned 502 after ~11s; without descriptionHTML the same
page of 100 returns in ~2.2s.

Author: edw1nzhao

backend/plugins/github_graphql/tasks/release_collector.go

@@ -57,22 +57,21 @@ type GraphqlQueryReleaseTagCommit struct {
 }
 
 type GraphqlQueryRelease struct {
-	Author          GraphqlQueryReleaseAuthor    `graphql:"author"`
-	DatabaseID      int                          `graphql:"databaseId"`
-	Id              string                       `graphql:"id"`
-	CreatedAt       time.Time                    `graphql:"createdAt"`
-	Description     string                       `graphql:"description"`
-	DescriptionHTML string                       `graphql:"descriptionHTML"`
-	IsDraft         bool                         `graphql:"isDraft"`
-	IsLatest        bool                         `graphql:"isLatest"`
-	IsPrerelease    bool                         `graphql:"isPrerelease"`
-	Name            string                       `graphql:"name"`
-	PublishedAt     *time.Time                   `graphql:"publishedAt"`
-	ResourcePath    string                       `graphql:"resourcePath"`
-	TagName         string                       `graphql:"tagName"`
-	TagCommit       GraphqlQueryReleaseTagCommit `graphql:"tagCommit"`
-	UpdatedAt       time.Time                    `graphql:"updatedAt"`
-	URL             string                       `graphql:"url"`
+	Author       GraphqlQueryReleaseAuthor    `graphql:"author"`
+	DatabaseID   int                          `graphql:"databaseId"`
+	Id           string                       `graphql:"id"`
+	CreatedAt    time.Time                    `graphql:"createdAt"`
+	Description  string                       `graphql:"description"`
+	IsDraft      bool                         `graphql:"isDraft"`
+	IsLatest     bool                         `graphql:"isLatest"`
+	IsPrerelease bool                         `graphql:"isPrerelease"`
+	Name         string                       `graphql:"name"`
+	PublishedAt  *time.Time                   `graphql:"publishedAt"`
+	ResourcePath string                       `graphql:"resourcePath"`
+	TagName      string                       `graphql:"tagName"`
+	TagCommit    GraphqlQueryReleaseTagCommit `graphql:"tagCommit"`
+	UpdatedAt    time.Time                    `graphql:"updatedAt"`
+	URL          string                       `graphql:"url"`
 }
 
 var CollectReleaseMeta = plugin.SubTaskMeta{