Add an alert if shoot is for too long in a pending state

[tobiscr]

Description

We have to react in case the Shoot is staying endless in Pending state.

We are currently not able to detect if the process is staying too long in this state. We have to gain more experiences how often such cases are happening and whether we should consider this sitiuation in our logic or keep it as incidental cases.

AC:

• Create a monitoring rule which fires an alert when the RuntimeCR stays in pending for longer than 45 m in