modified run_shifter to be thread safe and fixed the steps when image is shifted

requested review from @mhz1g21

assigned to @mhby1g21

requested review from @las1g21 and removed review request for @mhz1g21

requested review from @mhz1g21 and removed review request for @las1g21

requested review from @las1g21 and removed review request for @mhz1g21

approved this merge request

mentioned in commit c61149fd

merged