Seeding of random number streams used in TRTDigitizationTool::lateInitialize should not depend on the event number

Prior to the changes in this merge request, the random number streams used in the TRTDigitizationTool::lateInitialize method would be seeded based on the event number of the first event number in the job. The results of these calls are effectively cached for the whole job though, this meant that output was not reproducible if events in a file were skipped. The random number streams involved are now seeded based on a configurable property of TRTDigitizationTool, so the results of TRTDigitizationTool::lateInitialize should be independent of which event is run first in the job.

Should be merged after !28583 (merged).