slapgrid: fix invocation of bootstrapBuildout
as stated in https://lab.nexedi.com/nexedi/slapos.buildout/merge_requests/25#note_149333 we should never overwrite os.environ variable. Instead change the environment only when calling SlapPopen
as stated in https://lab.nexedi.com/nexedi/slapos.buildout/merge_requests/25#note_149333 we should never overwrite os.environ variable. Instead change the environment only when calling SlapPopen