Plan output not properly formatted

[Mmasson-01]

Describe the bug Capturing the terragrunt plan output to use it into a comment is not properly formatted. The plan output is on a single line.

To Reproduce Steps to reproduce the behavior, code snippets and examples which can be used to reproduce the issue.

    - name: Check terragrunt HCL
      uses: gruntwork-io/terragrunt-action@v1
      id: fmt
      with:
        tf_version: ${{ inputs.tf_version }}
        tg_version: ${{ inputs.tg_version }}
        tg_dir: ${{ inputs.workdir }}
        tg_command: 'hclfmt --terragrunt-check --terragrunt-diff'

    - name: Plan
      id: plan
      uses: gruntwork-io/terragrunt-action@v1
      with:
        tg_comment: 1
        tf_version: ${{ inputs.tf_version }}
        tg_version: ${{ inputs.tg_version }}
        tg_dir: ${{ inputs.workdir }}
        tg_command: 'plan'

    - uses: actions/github-script@v6
      if: github.event_name == 'pull_request'
      env:
        PLAN: "terraform\n${{ steps.plan.outputs.tg_action_output }}"
      with:
        github-token: ${{ inputs.GITHUB_TOKEN }}
        script: |
          // 1. Retrieve existing bot comments for the PR
          const { data: comments } = await github.rest.issues.listComments({
            owner: context.repo.owner,
            repo: context.repo.repo,
            issue_number: context.issue.number,
          })
          const botComment = comments.find(comment => {
            return comment.user.type === 'Bot' && comment.body.includes('Terragrunt Format and Style')
          })

          // 2. Prepare format of the comment
          const output = `#### Terragrunt Format and Style 🖌\`${{ steps.fmt.outcome }}\`

          #### Terragrunt Plan 📖\`${{ steps.plan.outcome }}\`

          <details><summary>Show Plan</summary>

          \`\`\`\n
          ${{ steps.plan.outputs.tg_action_output }}
          \`\`\`

          </details>

          *Pusher: @${{ github.actor }}, Action: \`${{ github.event_name }}\`, Workflow: \`${{ github.workflow }}\`*`;

          // 3. If we have a comment, update it, otherwise create a new one
          if (botComment) {
            github.rest.issues.updateComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              comment_id: botComment.id,
              body: output
            })
          } else {
            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: output
            })
          }

Expected behavior Should output the plan formatted as shown in the action log:

Nice to have

• [X] Terminal output
• [X] Screenshots

Versions

• Terragrunt Action version: v1
• Environment details (Terragrunt version, Terraform version, etc.):
  • tg version: 0.46.3
  • tf version: 1.5.6

Additional context I've tried a few things to output in the proper format but no luck so far.