Extract actions on new pull request from models to pulls service and move code.gitea.io/gitea/modules/pull to code.gitea.io/gitea/services/pull (#8218)

* extract actions on new pull request from models to pulls service

* improve code

* move code.gitea.io/gitea/modules/pull to code.gitea.io/gitea/services/pull

* fix fmt

* Rename pulls.go to pull.go

models/pull.go

@@ -700,33 +700,6 @@ func NewPullRequest(repo *Repository, pull *Issue, labelIDs []int64, uuids []str
 		return fmt.Errorf("Commit: %v", err)
 	}
 
-	if err = NotifyWatchers(&Action{
-		ActUserID: pull.Poster.ID,
-		ActUser:   pull.Poster,
-		OpType:    ActionCreatePullRequest,
-		Content:   fmt.Sprintf("%d|%s", pull.Index, pull.Title),
-		RepoID:    repo.ID,
-		Repo:      repo,
-		IsPrivate: repo.IsPrivate,
-	}); err != nil {
-		log.Error("NotifyWatchers: %v", err)
-	}
-
-	pr.Issue = pull
-	pull.PullRequest = pr
-	mode, _ := AccessLevel(pull.Poster, repo)
-	if err = PrepareWebhooks(repo, HookEventPullRequest, &api.PullRequestPayload{
-		Action:      api.HookIssueOpened,
-		Index:       pull.Index,
-		PullRequest: pr.APIFormat(),
-		Repository:  repo.APIFormat(mode),
-		Sender:      pull.Poster.APIFormat(),
-	}); err != nil {
-		log.Error("PrepareWebhooks: %v", err)
-	} else {
-		go HookQueue.Add(repo.ID)
-	}
-
 	return nil
 }