Fix and clarify redirect HTTP logic

redirect-http seemed to suggest the Pages daemon would redirect from HTTPS to HTTP, but it seems that the opposite was implied.

Fixes issue manifested by https://gitlab.com/gitlab-org/omnibus-gitlab/merge_requests/1348

helpers_test.go

@@ -49,12 +49,6 @@ var InsecureHTTPSClient = &http.Client{
 	},
 }
-var CheckRedirectClient = &http.Client{
-	CheckRedirect: func(req *http.Request, via []*http.Request) error {
-		return http.ErrUseLastResponse
-	},
-}
-
 var CertificateFixture = `-----BEGIN CERTIFICATE-----
 MIICWDCCAcGgAwIBAgIJAMyzCfoGEwVNMA0GCSqGSIb3DQEBCwUAMEUxCzAJBgNV
 BAYTAkFVMRMwEQYDVQQIDApTb21lLVN0YXRlMSEwHwYDVQQKDBhJbnRlcm5ldCBX
@@ -232,5 +226,6 @@ func GetRedirectPage(t *testing.T, spec ListenSpec, host, urlsuffix string) (*ht
 	req.Host = host
-	return CheckRedirectClient.Do(req)
+	rt := &http.Transport{}
+	return rt.RoundTrip(req)
 }