Changes in fedora 42 necessitates a slight change in installer.sh, or an extra step for fedora users

### Changes in fedora 42 necessitates a slight change in installer.sh, or an extra step for fedora users

This fix is for people who can for example do this:

```
terminal:~$ virsh -c qemu:///system start RDPWindows
Domain "RDPWindows" started
```

or this:

```
terminal:~$ sudo virsh start RDPWindows
Domain "RDPWindows" started
```

But not this, as they get an error:

```
terminal:~$ virsh start RDPWindows
error: failed to retrieve domain 'RDPWindows'

```

### The fix, and the why

There has been a change to how Virsh behaves in at least fedora 42; maybe even earlier. It no longer defaults to looking for system wide VMs which breaks the installer.sh script.

One solution is to do one extra step before launching the installer.sh:

```
terminal:~$ nano ~/.bashrc
terminal:~$ source ~/.bashrc
```

add
`
export VIRSH_DEFAULT_CONNECT_URI="qemu:///system"`

To the end of the file. It will make Virsh default to looking for the system wide RDP accessible VMs, which winapps rely on.