JITL Jobs should not take more time for execution depending on the number of JobScheduler Objects in the live folder

Current Situation

• When using a JITL Job in a job chain then the duration depends on the number of JobScheduler objects in the live folder.
• Example: the JobSchedulerExistsFile job takes 6s if there are 8 JobScheduler objects in the live folder and 24s if there are 630 JobScheduler objects in the live folder

Desired Behavior

• The number of JobScheduler objects should not affect the execution time.
• An exception to this rule are jobs that make use of the JobScheduler XML API to get information about the current status of other objects such as the JobSchedulerSynchronizeJobChains job.

Maintaner Notes

• This problem reflects an issue that is solved with JS-1248