More db.DefaultContext refactor (#27265)

Part of #27065

This PR touches functions used in templates. As templates are not static
typed, errors are harder to find, but I hope I catch it all. I think
some tests from other persons do not hurt.

services/issue/comments.go

@@ -84,7 +84,7 @@ func UpdateComment(ctx context.Context, c *issues_model.Comment, doer *user_mode
 		}
 	}
 
-	if err := issues_model.UpdateComment(c, doer); err != nil {
+	if err := issues_model.UpdateComment(ctx, c, doer); err != nil {
 		return err
 	}