proc mounted with wrong permission

`dr-xr-xr-x 235 nobody root 0 Mar 16 01:50 proc`
from #138

currently, we're using `mount -t proc proc /proc`

Attempted solution
```
unshare --mount --map-root-user --pid --fork /bin/bash
mkdir proc
mount -t proc -o uid=0,gid=0 none proc
```
but we get
`mount: a: wrong fs type, bad option, bad superblock on none, missing codepage or helper program, or other error.`