Make cloudbuild trigger disabled field a bool

[emilymye]

String --> bool

Fixes hashicorp/terraform-provider-google#3299

---

[all]

[terraform]

Make cloudbuild trigger disabled field a bool

[terraform-beta]

Make cloudbuild trigger disabled field a bool

[ansible]

[inspec]

[emilymye]

make testacc TEST=./google TESTARGS='--run="TestAccCloudBuildTrigger"'
==> Checking source code against gofmt...
==> Checking that code complies with gofmt requirements...
TF_ACC=1 TF_SCHEMA_PANIC_ON_ERROR=1 go test ./google -v --run="TestAccCloudBuildTrigger" -timeout 240m -ldflags="-X=github.com/terraform-providers/terraform-provider-google/version.ProviderVersion=acc"
=== RUN   TestAccCloudBuildTrigger_cloudbuildTriggerFilenameExample
=== PAUSE TestAccCloudBuildTrigger_cloudbuildTriggerFilenameExample
=== RUN   TestAccCloudBuildTrigger_basic
=== PAUSE TestAccCloudBuildTrigger_basic
=== RUN   TestAccCloudBuildTrigger_disable
=== PAUSE TestAccCloudBuildTrigger_disable
=== RUN   TestAccCloudBuildTrigger_fullStep
=== PAUSE TestAccCloudBuildTrigger_fullStep
=== CONT  TestAccCloudBuildTrigger_cloudbuildTriggerFilenameExample
=== CONT  TestAccCloudBuildTrigger_fullStep
=== CONT  TestAccCloudBuildTrigger_disable
=== CONT  TestAccCloudBuildTrigger_basic
--- PASS: TestAccCloudBuildTrigger_fullStep (1.94s)
--- PASS: TestAccCloudBuildTrigger_cloudbuildTriggerFilenameExample (2.34s)
--- PASS: TestAccCloudBuildTrigger_disable (3.90s)
--- PASS: TestAccCloudBuildTrigger_basic (3.97s)
PASS
ok  	github.com/terraform-providers/terraform-provider-google/google	4.337s

[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 ce5a9d7699727a008fee756261dc563340e2a545.

Pull request statuses

No diff detected in terraform-google-conversion.
No diff detected in Inspec.

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#595
depends: hashicorp/terraform-provider-google#3398
depends: modular-magician/ansible#230

[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 b8ae7a6.

Pull request statuses

terraform-provider-google-beta already has an open PR.
No diff detected in terraform-google-conversion.
terraform-provider-google already has an open PR.
Ansible already has an open PR.
No diff detected in Inspec.

New Pull Requests

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