removed redundant instructions from base grep Dockerfile
removed redundant instructions from base grep Dockerfile

ChrisTimperley/RepairBox,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/RepairBox,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/RepairBox,ChrisTimperley/RepairBox,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/AutomatedRepairBenchmarks.c,squaresLab/RepairBox,ChrisTimperley/RepairBox,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/RepairBox,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/RepairBox,ChrisTimperley/RepairBox,ChrisTimperley/RepairBox,ChrisTimperley/RepairBox,ChrisTimperley/AutomatedRepairBenchmarks.c