Leftover processes after running make test

[maelvls]

Sometimes (for example when the CRD file isn't found), the test would stop immediately after envtest.Start, meaning that the t.Cleanup block wouldn't run and the two new processes would be left over after the test process would end.

Credit for identifying this bug and fixing goes to Richard Wall in (1).

[maelvls]

I was slightly annoyed that running go test would always end up with the unhelpful message:

unable to start control plane itself: failed to start the controlplane. retried 5 times: fork/exec /usr/local/kubebuilder/bin/etcd: no such file or directory

So I added this quick fix to help whoever is running this test to sort things out.

[wallrj]

Thanks @maelvls

I tried it and it worked.

$ go test ./pkg/client/...
--- FAIL: TestVenConnClient_PostDataReadingsWithOptions (0.00s)
    --- FAIL: TestVenConnClient_PostDataReadingsWithOptions/valid_accessToken (0.00s)
        client_venconn_test.go:340: KUBEBUILDER_ASSETS isn't set. You can run this test using `make test`.
            But if you prefer not to use `make`, run these two commands first:
                make _bin/tools/{kube-apiserver,etcd}
                export KUBEBUILDER_ASSETS=$PWD/_bin/tools
    --- FAIL: TestVenConnClient_PostDataReadingsWithOptions/error_when_the_apiKey_field_is_used (0.00s)
        client_venconn_test.go:340: KUBEBUILDER_ASSETS isn't set. You can run this test using `make test`.
            But if you prefer not to use `make`, run these two commands first:
                make _bin/tools/{kube-apiserver,etcd}
                export KUBEBUILDER_ASSETS=$PWD/_bin/tools
    --- FAIL: TestVenConnClient_PostDataReadingsWithOptions/error_when_the_tpp_field_is_used (0.00s)
        client_venconn_test.go:340: KUBEBUILDER_ASSETS isn't set. You can run this test using `make test`.
            But if you prefer not to use `make`, run these two commands first:
                make _bin/tools/{kube-apiserver,etcd}
                export KUBEBUILDER_ASSETS=$PWD/_bin/tools
FAIL
FAIL    github.com/jetstack/preflight/pkg/client        0.026s
FAIL

$ make _bin/tools/{kube-apiserver,etcd}
make: '_bin/tools/kube-apiserver' is up to date.
make: '_bin/tools/etcd' is up to date.

$ export KUBEBUILDER_ASSETS=$PWD/_bin/tools

$ go test ./pkg/client/...
ok      github.com/jetstack/preflight/pkg/client        18.790s

/approve
/lgtm