provider/statuscake: Fixing up the StatusCake acceptance tests (#12006)

provider/statuscake: Fixing up the StatusCake acceptance tests (#12006)

```
% make testacc TEST=./builtin/providers/statuscake                                                      2 ↵ ✹
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/02/16 15:30:40 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/statuscake -v  -timeout 120m
=== RUN   TestProvider
--- PASS: TestProvider (0.00s)
=== RUN   TestProvider_impl
--- PASS: TestProvider_impl (0.00s)
=== RUN   TestAccStatusCake_basic
--- PASS: TestAccStatusCake_basic (2.14s)
=== RUN   TestAccStatusCake_tcp
--- PASS: TestAccStatusCake_tcp (1.66s)
=== RUN   TestAccStatusCake_withUpdate
--- PASS: TestAccStatusCake_withUpdate (3.62s)
PASS
ok  	github.com/hashicorp/terraform/builtin/providers/statuscake	7.435s
```