Update firebase token in Travis

[alexjball]

The deployment token is expired, I think. Deployment fails on travis. We need to update the FIREBASE_TOKEN variable in travis settings. I don't have permissions. Manual deployment still works.

https://travis-ci.org/github/codeforboston/migrant_service_map/builds/759489651

[maiam6242]

@alexjball was this ever figured out? I'm trying to deploy bit having a lot of trouble