Add expiration policy to pubsub subscription resource

[tysen]

Fixes hashicorp/terraform-provider-google#2507

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[all]

[terraform]

[terraform-beta]

[ansible]

[inspec]

[modular-magician]

Hi! I'm the modular magician, I work on Magic Modules.
This PR seems not to have generated downstream PRs before, as of 21fecd64710dec363c572b58274c8040bd7ca722.

Pull request statuses

New Pull Requests

I built this PR into one or more new PRs on other repositories, and when those are closed, this PR will also be merged and closed.
depends: hashicorp/terraform-provider-google-beta#648
depends: GoogleCloudPlatform/terraform-google-conversion#68
depends: hashicorp/terraform-provider-google#3525
depends: modular-magician/ansible#240
depends: modular-magician/inspec-gcp#153

[rileykarson]

Can you update one of the PubSub examples (https://github.com/GoogleCloudPlatform/magic-modules/tree/master/templates/terraform/examples) to use the new field so users see how to configure it + we test it?

It could also be worth specifying in the ttl field docs how it's specified.

[tysen]

Added both, along with a DSF for expirationPolicy.ttl.

[rileykarson]

Nice work! LGTM.

[modular-magician]

Hi! I'm the modular magician, I work on Magic Modules.
I see that this PR has already had some downstream PRs generated. Any open downstreams are already updated to your most recent commit, 923e3e9.

Pull request statuses

terraform-provider-google-beta already has an open PR.
terraform-google-conversion already has an open PR.
terraform-provider-google already has an open PR.
Ansible already has an open PR.
InSpec already has an open PR.

New Pull Requests

I didn't open any new pull requests because of this PR.