Use pre-setup & post-setup as suggested in review

Author: JKrag

bisect/setup.sh

@@ -1,8 +1,7 @@
 #!/bin/bash
 source ../utils/utils.sh
 
-make-exercise-repo
-config-local-username
+pre-setup # Make exercise repo, and setup necessary.
 
 echo '#! /usr/bin/env bash' > 'test.sh'
 echo 'if [[ $(( $(find * | wc -l) + 10 )) -gt 32 ]] ;then' >> 'test.sh'
@@ -24,3 +23,4 @@ do
   git commit -m $i
 done
 
+post-setup

bisect/verify.sh

@@ -1,6 +1,6 @@
 #! /usr/bin/env sh
 
-cd exercise
+cd exercise || exit
 if [ "$(git log -1 --format='%s' refs/bisect/bad -- )" = '22' ] ; then
   echo "You managed to find the bad commit with bisect"
 else