Fix code scanning alert - Potentially unsafe external link

[joshbeckman]

Tracking issue for:

• [ ] https://github.com/joshbeckman/notes/security/code-scanning/1
• [ ] https://github.com/joshbeckman/notes/security/code-scanning/2
• [ ] https://github.com/joshbeckman/notes/security/code-scanning/3
• [ ] https://github.com/joshbeckman/notes/security/code-scanning/4