[BUG]: support other users in enable-usb-sync.sh

[CWempe]

Describe the bug

I installed photobooth on a freshly installed pi today.
As far as I know the user pi is no longer the default user for Raspberry Pi OS.
see: https://www.golem.de/news/bastelrechner-raspberry-pi-os-verwirft-den-standarduser-pi-2204-164535.html

But the script enable-usb-sync.sh does only work with the pi user.

Steps to reproduce the behavior

wget https://raw.githubusercontent.com/andi34/photobooth/dev/enable-usb-sync.sh
sudo bash enable-usb-sync.sh

Output:

--2022-05-01 22:42:30--  https://raw.githubusercontent.com/andi34/photobooth/dev/enable-usb-sync.sh
Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 2606:50c0:8001::154, 2606:50c0:8002::154, 2606:50c0:8003::154, ...
Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|2606:50c0:8001::154|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1696 (1.7K) [text/plain]
Saving to: ‘enable-usb-sync.sh’

enable-usb-sync.sh                                          100%[========================================================================================================================================>]   1.66K  --.-KB/s    in 0.001s

2022-05-01 22:42:31 (1.88 MB/s) - ‘enable-usb-sync.sh’ saved [1696/1696]

### Disabling automount for pi user
chown: invalid user: ‘pi:pi’

Expected behavior

Script should use the current user or ask for the user name.

Photobooth Version

3.3.0

Browser and browser version

Chrome 101

Operating System

Raspberry Pi OS 11

Did it work before?

No

Latest working version

No response

Additional context

I will try to correct the script for myself (quick and dirty).

[CWempe]

If anyone is wondering, you can use this command to replace the pi user with your own user.

sed -i 's/pi/my-new-user/g' enable-usb-sync.sh

[CWempe]

btw: I just realized I had not installed this fork, yet.
I was still using v2.1.0.

But this does not change this bug, I think.

[andi34]

Same applies to the installer. I am going to look at it as soon as I find enough time. Thanks for the report!