fixed: Seed video duration to the database without JSON

[mvp5464]

PR Fixes:

• 1 If video duration is empty, and anyone clicks on that video, It adds video duration to the database
• 2 Video thumbnail will have proper duration

Resolves #485

Checklist before requesting a review

• [x] I have performed a self-review of my code
• [x] I assure there is no similar/duplicate pull request regarding same issue

Screencast.webm

[mvp5464]

@hkirat sir, tried many methods (like seeding all videos in SSG, etc.) to seed duration, but this seems good. After old video duration is seeded then we can add duration when you upload the video, if needed (working on it).

• any suggestion or improvement sir.