Drop unused feature_filter_type experiment column

changelogs/unreleased/270409-experiment-cleanup-drop-feature-filter-type-column.yml

+---
+title: Drop unused feature_filter_type experiment column
+merge_request: 48221
+author:
+type: deprecated

db/post_migrate/20201120071303_drop_feature_filter_type_from_user_preferences.rb

+# frozen_string_literal: true
+
+class DropFeatureFilterTypeFromUserPreferences < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    with_lock_retries do
+      remove_column :user_preferences, :feature_filter_type
+    end
+  end
+
+  def down
+    with_lock_retries do
+      add_column :user_preferences, :feature_filter_type, :bigint
+    end
+  end
+end

db/schema_migrations/20201120071303

+9684403a075bd1ddf3ae9290ad9a39ed24f4624d99498f8b8ed567588c15e082
\ No newline at end of file

db/structure.sql

@@ -16886,7 +16886,6 @@ CREATE TABLE user_preferences (
     setup_for_company boolean,
     render_whitespace_in_code boolean,
     tab_width smallint,
-    feature_filter_type bigint,
     experience_level smallint,
     view_diffs_file_by_file boolean DEFAULT false NOT NULL,
     gitpod_enabled boolean DEFAULT false NOT NULL