Fix command substitution vulnerability in issue linking workflow

Problem Statement

The issue_comp_link-issue-to-pr.yml workflow fails when PR bodies contain backticks due to unquoted variable expansion in bash. When the PR body includes text like `change-detection: 'enabled'`, bash interprets the backticks as command substitution and attempts to execute the content as a command, resulting in exit code 127 (command not found).

Impact: The issue linking workflow fails for any PR with backticks in the description, preventing automatic issue-to-PR linking.

Example failure: https://github.com/dotCMS/core/actions/runs/22108485819/job/63897956233

Steps to Reproduce

1. Create a PR with backticks in the body, e.g.: `some-value`
2. The Add Issue to PR / link-issue workflow triggers
3. The "Debug workflow inputs" step fails with exit code 127
4. Error: ##[error]Process completed with exit code 127

Root cause location: .github/workflows/issue_comp_link-issue-to-pr.yml lines 38-44:

- name: Debug workflow inputs
  run: |
    echo "PR Body: ${{ inputs.pr_body }}"  # Backticks cause command substitution

Acceptance Criteria

• Fix the "Debug workflow inputs" step to properly escape/quote PR body content
• Validate fix with actionlint (available via mise - run actionlint .github/workflows/)
• Ensure all other steps that echo inputs are also properly escaped
• Test with a PR containing backticks, single quotes, and double quotes in the body

dotCMS Version

N/A - CI/CD infrastructure issue

Severity

Medium - Some functionality impacted

Links

• Related PR: https://github.com/dotCMS/core/pull/34680
• Failed workflow run: https://github.com/dotCMS/core/actions/runs/22108485819/job/63897956233

Start with .github/workflows/issue_comp_link-issue-to-pr.yml, especially the “Debug workflow inputs” step at lines 38-44, and inspect other steps that echo inputs. Run actionlint .github/workflows/ via mise, then test the workflow with PR bodies containing backticks, single quotes, and double quotes. Done means the workflow no longer fails with exit code 127 and all input output is safely handled.