Added the automatic active link when scrolled and fixed the testimonial issue

[Ananta2545]

This is in reference to #381

1. Added the automatic active link when scrolled:-

Whenever any section is scroll to then that corresponding navbar link is automatically active and is changed when next section is scrolled.

Before:-

issueVideo.mp4

After:-

Recording.2024-10-14.123306.1.mp4

2. Testimonial Issue:-

Testimonial section is not appearing in the original website

Before:-

After:-

Here the testimonial issue is Solved along with the active navbar feature.

Please accept my PR under GSSOC-EXTD and HACKTOBERFEST-2024.

Thanks!!!