feat: add support for tflint scanner for Terraform

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What does this MR do and why?

This update adds TFLint as a new code quality scanner to the existing suite of tools. TFLint is specifically designed to scan and lint Terraform code, helping identify issues in infrastructure-as-code files. The changes include adding a new template file for TFLint configuration, updating the main README to document the new scanner, and modifying the codequality-oss.yml file to include TFLint as an option. The TFLint scanner will automatically run when Terraform files (*.tf) are detected in the repository, generating code quality reports in the same format as the other scanners. Users can either use a custom configuration file (.tflint.hcl) or run with default settings if no configuration is provided..

This merge request is part of #7 (closed)