Fix old migrations failing because of new version of `strong_migrations`

Fixes #1099

db/migrate/20180402040909_create_report_notes.rb

@@ -8,7 +8,7 @@ class CreateReportNotes < ActiveRecord::Migration[5.1]
       t.timestamps
     end
 
-    add_foreign_key :report_notes, :reports, column: :report_id, on_delete: :cascade
-    add_foreign_key :report_notes, :accounts, column: :account_id, on_delete: :cascade
+    safety_assured { add_foreign_key :report_notes, :reports, column: :report_id, on_delete: :cascade }
+    safety_assured { add_foreign_key :report_notes, :accounts, column: :account_id, on_delete: :cascade }
   end
 end

db/migrate/20180707193142_migrate_filters.rb

@@ -41,7 +41,7 @@ class MigrateFilters < ActiveRecord::Migration[5.2]
         t.timestamps
       end
 
-      add_foreign_key :glitch_keyword_mutes, :accounts, on_delete: :cascade
+      safety_assured { add_foreign_key :glitch_keyword_mutes, :accounts, on_delete: :cascade }
     end
 
     CustomFilter.where(irreversible: true).find_each do |filter|