ci: Update dependabot to cover all terraform files

[tungbq]

Update https://github.com/tungbq/devops-basic/blob/main/.github/dependabot.yml
To cover all terraform files under https://github.com/tungbq/devops-basic/tree/main/topics/terraform

For example: topics/terraform/advanced/docker
Documentation: https://github.com/dependabot/dependabot-core

(NOTE: For now we only cover /topics/terraform/basic/aws-ec2)

[github-actions]

This issue is stale because it has been open for 30 days with no activity.

[github-actions]

This issue was closed because it has been inactive for 14 days since being marked as stale.