Add fred.stlouisfed.org to linkcheck_ignore

[Copilot]

The CI link checker reports timeouts (status 0) for FRED links in pandas.md — these are false positives caused by network restrictions in the CI environment, not actually broken links.

Change

• Added https://fred.stlouisfed.org/.* to linkcheck_ignore in lectures/_config.yml, matching both the root URL and all subpaths (e.g. /series/UNRATE)

linkcheck_ignore: [
  ...
  'https://fred.stlouisfed.org/.*'
]

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Broken Links Found in Documentation</issue_title>
<issue_description># Link Check Report

🚨 2 broken link(s) and 0 redirect(s) were found in the documentation.

Details:

• Repository: QuantEcon/lecture-python-programming.myst
• Workflow: Link Checker [Anaconda, Linux]
• Run ID: 23170125562
• Commit: f365972
• Branch: main
• Date: 2026-03-16T23:14:26.804Z

---

Link Check Summary

• Total broken links: 2
• Total redirects found: 0

Broken Links

./pandas.html - 2 broken link(s):
❌ https://fred.stlouisfed.org/ - Status: 0 (Timeout)
Link text: FRED
❌ https://fred.stlouisfed.org/series/UNRATE - Status: 0 (Timeout)
Link text: unemployment rate

---

Next Steps:

1. Review the broken links listed above
2. Update or remove broken links from the source files
3. Consider applying AI suggestions for better alternatives
4. Re-run the link check to verify fixes

Note: This issue was automatically created by the AI-Powered Link Checker Action.

Please close this issue once all broken links have been addressed.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Broken Links Found in Documentation #482

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