Add default value for DB_TLS in integration tests
Add default value for DB_TLS in integration tests

[#147717361](https://www.pivotaltracker.com/story/show/147717361)

Signed-off-by: Gaurab Dey <6eab2c4141d8485c934adabfb0522546caded7e6@pivotal.io>

barthy1/bosh,barthy1/bosh,barthy1/bosh,barthy1/bosh