Changed git clone strategy for CI tests.

Previously, it seems like build artifacts from previous runs (such as
.sch files and logs) were retained.  We need to make sure we have a
clean build.
7 jobs for develop in 102 minutes and 7 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build Libmesh
passed #7165
build_libmesh_job

00:11:40

 
  Configure Giraffe
passed #7166
configure_giraffe_job

00:00:18

 
  Build Giraffe
passed #7167
build_giraffe_job

00:11:22

 
  Run Giraffe
failed #7169
run_giraffe_parallel_job

passed #7168
run_giraffe_serial_job

01:18:45

 
  Verify Giraffe
skipped #7171
verify_giraffe_parallel_job
skipped #7170
verify_giraffe_serial_job
 
Name Stage Failure
failed
run_giraffe_parallel_job Run Giraffe There is an unknown failure, please try again
No job log