See if we can prevent cronjob from spawning if wordpress pod is not ready

We have a lot of errorring pods like this (site name removed from log):

-wordpress-1602165600-4nrk4        0/1     Error       0          70m
-wordpress-1602165600-f9f7v        0/1     Error       0          65m
-wordpress-1602165600-kltz9        0/1     Error       0          69m
-wordpress-1602165600-mcg8h        0/1     Error       0          68m
-wordpress-1602165600-rbfld        0/1     Error       0          69m
-wordpress-1602165600-swtlv        0/1     Error       0          69m
-wordpress-1602165960-7b77d        0/1     Error       0          58m
-wordpress-1602165960-7m9qf        0/1     Error       0          60m
-wordpress-1602165960-7mptp        0/1     Error       0          55m
-wordpress-1602165960-8kpz8        0/1     Error       0          61m
-wordpress-1602165960-dmwzw        0/1     Error       0          59m
-wordpress-1602165960-jpt8v        0/1     Error       0          62m
-wordpress-1602165960-mz896        0/1     Error       0          61m
-wordpress-1602166680-8tnq5        0/1     Error       0          49m
-wordpress-1602166680-bglkh        0/1     Error       0          45m
-wordpress-1602166680-dbx6k        0/1     Error       0          47m
-wordpress-1602166680-dhggt        0/1     Error       0          49m

These are cronjob pods that return errors when the WordPress is not ready yet. This also happens, for example, when you install a new wordpress. That means that a fresh install would give you a bunch of Errored pods in your pod overview, which is not nice. We should check if we can prevent the cronjob from spawning at all when the wordpress is not ready.