Raise Mastodon::HostValidationError when host for HTTP request is private (#6410)

app/lib/sidekiq_error_handler.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+class SidekiqErrorHandler
+  def call(*)
+    yield
+  rescue Mastodon::HostValidationError => e
+    Rails.logger.error "#{e.class}: #{e.message}"
+    Rails.logger.error e.backtrace.join("\n")
+    # Do not retry
+  end
+end