Fails to initialize container if the image has non-empty /mnt and the host has a symlink as /mnt

**Describe the bug**
It fails to initialize container if the image has non-empty `/mnt` and the host has a symlink as `/mnt`.

**Steps how to reproduce the behaviour**
1. Run `toolbox create -i image-with-non-empty-mnt`
2. Run `toolbox enter image-with-non-empty-mnt-latest`
3. See error

**Expected behaviour**
No error will happen.

**Actual behaviour**
It fails to initialize the container.

**Screenshots**
N/A

**Output of `toolbox --version` (v0.0.90+)**
`toolbox version 0.0.99.4`

**Toolbox package info (`rpm -q toolbox`)**
`toolbox-0.0.99.4-1.fc38.x86_64`

**Output of `podman version`**
```
Client: Podman Engine
Version: 4.7.0
API Version: 4.7.0
Go Version: go1.20.8
Built: Thu Sep 28 03:24:38 2023
OS/Arch: linux/amd64
```

**Podman package info (`rpm -q podman`)**
`podman-4.7.0-1.fc38.x86_64`

**Info about your OS**
Fedora Silverblue 38

**Additional context**
`/mnt` is a symlink to `/var/mnt` on the affected system.