我升级到 Terraform v0.12.16，现在我收到很多类似这样的消息：
Warning: Interpolation-only expressions are deprecated
on ../modules/test-notifier/test_notifier.tf line 27, in resource "aws_sns_topic_policy" "default":
27: arn = "${aws_sns_topic.default.arn}"
Terraform 0.11 and earlier required all non-constant expressions to be
provided via interpolation syntax, but this pattern is now deprecated. To
silence this warning, remove the "${ sequence from the start and the }"
sequence from the end of this expression, leaving just the inner expression.
Template interpolation syntax is still used to construct strings from
expressions when the template …terraform ×1