Displaying vain Vaccination Centers

[wweverma1]

@preetjdp I was exploring this project and I observed a small issue.

If I go to Find a Vaccine tab and select location, the app displays all the vaccination centers in that location.

I think this we should filter the response from server and display only that centers where vaccine is available because centers without vaccines are of no use to a user.

Also, I'm willing to work and on this project and fix this issue.