Don't validate post when saving in `Upload.migrate_to_new_scheme`.

Don’t validate post when saving in Upload.migrate_to_new_scheme.

diff --git a/app/models/upload.rb b/app/models/upload.rb
index ef92afe..08adb83 100644
--- a/app/models/upload.rb
+++ b/app/models/upload.rb
@@ -289,7 +289,7 @@ class Upload < ActiveRecord::Base
             remap_scope.each do |post|
               post.raw.gsub!(previous_url, upload.url)
               post.cooked.gsub!(previous_url, upload.url)
-    ! if post.changed?
+    !(validate: false) if post.changed?

GitHub sha: 9ec6ef85

Use update_all instead of save to select and update particular columns