Fix SECURITY.md commit_message drift

[akuzminsky]

Summary

• Update commit_message from "Add SECURITY.md" to "Update SECURITY.md" to match Terraform state and eliminate drift across 48 repos
• Restore template_repo for terraform-aws-org-governance which was genuinely created from a template

Context

Depends on #270. After the template drift fix, 49 resources still showed drift — 48 security_md resources with a cosmetic commit_message mismatch and 1 repo (org-governance) that shouldn't have had its template removed.

Expected plan after both PRs

2 changes: no-op commits to terraform-aws-org-governance and terraform-module-template to sync their commit_message in state. After that, plans will be clean.

Test plan

• CI plan shows only 2 security_md commit_message changes (org-governance + template repo)
• No other drift

🤖 Generated with Claude Code

[github-actions]

State s3://infrahouse-github-control-state/terraform.tfstate

Affected resources counts

Success	Add	🟡 Change	Destroy
✅	0	2	0

Affected resources by action

Action	Resources
🟡	module.repos["terraform-aws-org-governance"].github_repository_file.security_md[0]
🟡	module.template_terraform_module.github_repository_file.security_md[0]

STDOUT

Terraform used the selected providers to generate the following execution
plan. Resource actions are indicated with the following symbols:
  ~ update in-place

Terraform will perform the following actions:

  # module.repos["terraform-aws-org-governance"].github_repository_file.security_md[0] will be updated in-place
  ~ resource "github_repository_file" "security_md" {
      ~ commit_message      = "Add SECURITY.md" -> "Update SECURITY.md"
        id                  = "terraform-aws-org-governance/SECURITY.md"
        # (7 unchanged attributes hidden)
    }

  # module.template_terraform_module.github_repository_file.security_md[0] will be updated in-place
  ~ resource "github_repository_file" "security_md" {
      ~ commit_message      = "Add SECURITY.md" -> "Update SECURITY.md"
        id                  = "terraform-module-template/SECURITY.md"
        # (7 unchanged attributes hidden)
    }

Plan: 0 to add, 2 to change, 0 to destroy.

─────────────────────────────────────────────────────────────────────────────

Saved the plan to: tf.plan

To perform exactly these actions, run the following command to apply:
    terraform apply "tf.plan"

metadata

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