fix: handle broken links in community testimonials section

[Preksha0401]

Related Tickets & Documents

Fixes #3621

Description

This PR fixes inconsistent click behavior in the “What our community thinks” section
of the blog where some testimonial cards did not redirect to any page.

The issue was caused by missing or invalid external URLs in the testimonial data,
resulting in dead or unresponsive clicks.

Changes

• Added validation for external testimonial links
• Prevented navigation when a link is missing or invalid
• Improved UX by visually disabling non-clickable testimonial cards

Type of Change

• Chore (maintenance, refactoring, tooling updates)
• Bug fix (non-breaking change that fixes an issue)
• New feature (change that adds functionality)
• Breaking Change (may require updates in existing code)
• UI improvement (visual or design changes)
• Performance improvement (optimization or efficiency enhancements)
• Documentation update (changes to README, guides, etc.)
• CI (updates to continuous integration workflows)
• Revert (undo a previous commit or merge)

Testing

• Manually verified testimonial cards with valid links open in a new tab
• Verified cards with invalid or missing links do not trigger navigation
• Ensured no console or TypeScript errors were introduced

Environment and Dependencies

• New Dependencies: None
• Configuration Changes: None

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added corresponding tests
• I have run the build command to ensure there are no build errors
• My changes have been tested across relevant browsers/devices
• For UI changes, I've included visual evidence of my changes