Add CPU Load Calibration for Search Log Downloads to Reduce High CPU Usage

[marevol]

When downloading search logs, the current implementation can lead to high CPU usage, causing performance issues. To mitigate this, I have added a mechanism to check the CPU load and wait until it reduces to an acceptable level before continuing the download process. The changes involve updating the AdminBackupAction class and SystemHelper class to include CPU load calibration logic. Additionally, a new configuration property index.backup.log.load.timeout has been added to specify the timeout for this calibration.