Update pod-lifecycle.md

Default for periodSeconds field of startupProbe resource is 10 seconds.

$ kubectl explain pod.spec.containers.startupProbe.periodSeconds
KIND:     Pod
VERSION:  v1

FIELD:    periodSeconds <integer>

DESCRIPTION:
     How often (in seconds) to perform the probe. Default to 10 seconds. Minimum
     value is 1.

Author: PrakherS

content/en/docs/concepts/workloads/pods/pod-lifecycle.md

@@ -325,7 +325,7 @@ a time longer than the liveness interval would allow.
 If your container usually starts in more than
 `initialDelaySeconds + failureThreshold × periodSeconds`, you should specify a
 startup probe that checks the same endpoint as the liveness probe. The default for
-`periodSeconds` is 30s. You should then set its `failureThreshold` high enough to
+`periodSeconds` is 10s. You should then set its `failureThreshold` high enough to
 allow the container to start, without changing the default values of the liveness
 probe. This helps to protect against deadlocks.