I keep getting this warning about PEX_ROOT inside a lambda docker image. This is after I have configured a custom location and provided read/write permissions. Not sure what I am missing

/function/service.pex/.bootstrap/pex/variables.py:582: PEXWarning: PEX_ROOT is configured as /pex_root but that path is un-writeable, falling back to a temporary PEX_ROOT of /tmp/tmpxcb25rwu which will hurt performance.