Change file permissions of scp/sftp test asset
Change file permissions of scp/sftp test asset

* On linux the `0664` file permission will give write permission to the
current users group. When scping the file into a container, this
permission gets dropped as the group does not exist. On OSX, the group
is not given write permission to the generated file so this is not a
concern. On the errand VM, the vcap group exists in both the container
and the VM, so it is able to transfer the permissions correctly.

[#119334663]

Signed-off-by: James Myers <44cbd4b2784f900a6fede6279d0b7fdcbfaa89f5@pivotal.io>

matt-royal/cf-acceptance-tests,matt-royal/cf-acceptance-tests,matt-royal/cf-acceptance-tests,matt-royal/cf-acceptance-tests,matt-royal/cf-acceptance-tests,matt-royal/cf-acceptance-tests,matt-royal/cf-acceptance-tests,matt-royal/cf-acceptance-tests