Sleep longer if request speed is over github limitation (#9335)

* Sleep longer if request speed is over github limitation

* improve code

* remove unused code

* fix lint

* Use github's rate limit remain value to determine how long to sleep

* Save reset time when finished github api request

* fix bug

* fix lint

* Add context.Context for sleep

* fix test

* improve code

* fix bug and lint

* fix import order

modules/migrations/base/downloader.go

@@ -6,6 +6,7 @@
 package base
 
 import (
+	"context"
 	"time"
 
 	"code.gitea.io/gitea/modules/structs"
@@ -13,6 +14,7 @@ import (
 
 // Downloader downloads the site repo informations
 type Downloader interface {
+	SetContext(context.Context)
 	GetRepoInfo() (*Repository, error)
 	GetTopics() ([]string, error)
 	GetMilestones() ([]*Milestone, error)
@@ -30,6 +32,10 @@ type DownloaderFactory interface {
 	GitServiceType() structs.GitServiceType
 }
 
+var (
+	_ Downloader = &RetryDownloader{}
+)
+
 // RetryDownloader retry the downloads
 type RetryDownloader struct {
 	Downloader
@@ -46,6 +52,11 @@ func NewRetryDownloader(downloader Downloader, retryTimes, retryDelay int) *Retr
 	}
 }
 
+// SetContext set context
+func (d *RetryDownloader) SetContext(ctx context.Context) {
+	d.Downloader.SetContext(ctx)
+}
+
 // GetRepoInfo returns a repository information with retry
 func (d *RetryDownloader) GetRepoInfo() (*Repository, error) {
 	var (