Fix 500 error when adding PR comment (#29622)

Author: wxiaoguang

routers/web/repo/pull_review.go

@@ -10,6 +10,7 @@ import (
 
 	issues_model "code.gitea.io/gitea/models/issues"
 	pull_model "code.gitea.io/gitea/models/pull"
+	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/base"
 	"code.gitea.io/gitea/modules/json"
 	"code.gitea.io/gitea/modules/log"
@@ -19,6 +20,7 @@ import (
 	"code.gitea.io/gitea/services/context/upload"
 	"code.gitea.io/gitea/services/forms"
 	pull_service "code.gitea.io/gitea/services/pull"
+	user_service "code.gitea.io/gitea/services/user"
 )
 
 const (
@@ -203,6 +205,10 @@ func renderConversation(ctx *context.Context, comment *issues_model.Comment, ori
 		return
 	}
 	ctx.Data["AfterCommitID"] = pullHeadCommitID
+	ctx.Data["CanBlockUser"] = func(blocker, blockee *user_model.User) bool {
+		return user_service.CanBlockUser(ctx, ctx.Doer, blocker, blockee)
+	}
+
 	if origin == "diff" {
 		ctx.HTML(http.StatusOK, tplDiffConversation)
 	} else if origin == "timeline" {