Added sample.json to demonstrate how to list in sample gallery

[hugoabernier]

Please review this PR with @natalie-pienkowska in regards to listing the independent connectors in the sample galleries.

[natalie-pienkowska]

@sriyen-msft This is something we're working on as part of Independent Publisher connectors. I will work with Mahbub to see if this first in :)

[mamurshe]

I approved as the code is good to have. I will sync with Natalie to determine in what capacity we can publish this in sample gallery.

[Amjed-Ayoub]

[[certify-connector]]

[vmanoharas]

Hello @hugoabernier,

I hope you are doing well. As this connector is already certified and available in our internal repo. Hence closing this PR.