Undo now-unused change to ignore minio diff

* we tested and confirmed that the `rollback` change does not show up
when running the build script.

[#173736483](https://www.pivotaltracker.com/story/show/173736483)

Co-authored-by: Renee Chu <rchu@vmware.com>

ci/tasks/check-vendir-sync/task.sh

@@ -32,13 +32,6 @@ for dir in * ; do
   if [[ -d "$dir" ]] ; then
     cd $dir
     ./build.sh
-    if [[ $dir = "minio" ]] ; then
-      # Ignore the change to the `rollme` random value
-      minio_rendered_file="$DIR/config/minio/_ytt_lib/minio/rendered.yml"
-      if [[ $(git diff --unified=0 "$minio_rendered_file" | egrep "^(\+|-) " | grep -v rollme | wc -l) == 0 ]] ; then
-        git checkout "$minio_rendered_file"
-      fi
-    fi
     cd ..
   fi
 done