Adding new bbtests.env var and conditional script tests

Adding bbtests.scripts.env variable to conditionally enable/disable script tests. Because of Istio mTLS STRICT PeerAuthentication curl commands from a non-injected pod within a BB CI Pipeline will always fail. They will succeed in a non-injected package pipeline. All tests will still be ran, Cypress in BB CI and Script tests in Package CI.

See associated BB MR: https://repo1.dso.mil/platform-one/big-bang/bigbang/-/jobs/12689599