Add support for Terraform v1.9

[wata727]

Introduction

Terraform v1.9 added the following features related to TFLint.

• templatestring function
  • https://github.com/hashicorp/terraform/pull/34968
  • https://github.com/hashicorp/terraform/pull/35224
  • https://github.com/hashicorp/terraform/pull/35285
• https://github.com/hashicorp/terraform/pull/35180

Proposal

Update the embedded Terraform fork to v1.9.

References

• https://github.com/hashicorp/terraform/releases/tag/v1.9.0
• https://github.com/terraform-linters/tflint/issues/1878