caddy-frontend: Fetch CSR id only if not available yet

CSR id shall be requested only when it's not available yet, as otherwise it
contacts caucase server needlessly, and in some circumstances it can result
with bogus new CSR.
56 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
failed Cloudooo.UnitTest-Master

00:08:14

passed SlapOS.Eggs.UnitTest-Master.Python2

00:11:43

passed SlapOS.Eggs.UnitTest-Master.Python3

00:13:39

passed SlapOS.SlapRunner.ResilienceTest-Master

00:24:34

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:31:56

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

05:42:37

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

04:15:29

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

08:59:37

passed SlapOS.Eggs.UnitTest-Master.Python2

00:11:33

passed SlapOS.Eggs.UnitTest-Master.Python2

00:11:53

passed SlapOS.Eggs.UnitTest-Master.Python2

00:20:40

passed SlapOS.Eggs.UnitTest-Master.Python2

00:32:43

passed SlapOS.Eggs.UnitTest-Master.Python2

00:13:10

passed SlapOS.Eggs.UnitTest-Master.Python2

00:20:16

passed SlapOS.Eggs.UnitTest-Master.Python2

00:11:27

passed SlapOS.Eggs.UnitTest-Master.Python2

00:11:21

passed SlapOS.Eggs.UnitTest-Master.Python2

00:11:31

passed SlapOS.Eggs.UnitTest-Master.Python2

00:11:47

passed SlapOS.Eggs.UnitTest-Master.Python2

00:11:24

passed SlapOS.Eggs.UnitTest-Master.Python2

00:11:29

passed SlapOS.Eggs.UnitTest-Master.Python3

00:13:54

passed SlapOS.Eggs.UnitTest-Master.Python3

00:12:08

passed SlapOS.Eggs.UnitTest-Master.Python3

00:14:11

passed SlapOS.Eggs.UnitTest-Master.Python3

00:13:14

passed SlapOS.Eggs.UnitTest-Master.Python3

00:12:09

passed SlapOS.Eggs.UnitTest-Master.Python3

00:12:46

passed SlapOS.Eggs.UnitTest-Master.Python3

00:14:38

passed SlapOS.Eggs.UnitTest-Master.Python3

00:12:23

passed SlapOS.Eggs.UnitTest-Master.Python3

01:19:13

passed SlapOS.Eggs.UnitTest-Master.Python3

00:12:50

passed SlapOS.SlapRunner.ResilienceTest-Master

00:21:53

passed SlapOS.SlapRunner.ResilienceTest-Master

00:23:58

passed SlapOS.SlapRunner.ResilienceTest-Master

00:23:01

passed SlapOS.SlapRunner.ResilienceTest-Master

00:23:14

passed SlapOS.SlapRunner.ResilienceTest-Master

00:22:22

passed SlapOS.SlapRunner.ResilienceTest-Master

00:23:03

passed SlapOS.SlapRunner.ResilienceTest-Master

00:23:28

passed SlapOS.SlapRunner.ResilienceTest-Master

00:22:46

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:27:35

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:29:50

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:27:59

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:30:16

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:28:55

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:27:10

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:28:32

failed SlapOS.SlapRunner.ResilienceTest-Master.ERP5

01:31:41

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python2

04:28:25

failed SlapOS.SoftwareReleases.IntegrationTest-Master.Python3

20:52:05

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

10:46:27

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

08:24:05

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

08:21:52

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

09:14:02

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

08:58:13

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

08:23:45

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

08:30:05

passed Wendelin.StandaloneDeploymentScriptTest-Debian.Buster.Master

08:49:58