The main goal here is to avoid using a global variable.
The greeting message _onBarcodeScanned bus can be stoped right after
the barcode_scanned as every time a barcode is scanned, it creates
a new instance of the greeting message.
Some other JS guidelines are also applied here.
Special thanks to Martin Geubelle (@mge-odoo) for helping me on this.
[TEST] hr_attendance : add test for multiple quick scan in kiosk mode
Glorious thanks to @RomainLibert who fu**s off his brain to help me
understand what was really going on and how to simulate the
functional behaviour of Greeting Message kiosk stuff.
Task ID 1878251
Closes PR #27127
David Beguin
bbc7e9586d