updating tests to remove test.gov.uk

Now using dev.gov.uk as per https://github.com/alphagov/plek/blob/master/CHANGELOG.md
updating whenever call to include govuk_setenv
updating whenever call to include govuk_setenv
Revert "updating whenever to inc govuk_setenv"

This reverts commit 3f3e3c54e3adb8a050259339759cff4d3ea8686d.
updating jenkins to use govuk_setenv