Can't open any page with mixed user locals

### What Happened?

Epiphany / GNOME Web won't load any page if you have mixed user locals. Same issue as reported in [StackExchange](https://elementaryos.stackexchange.com/questions/29856/epiphany-dont-work-if-you-have-mixed-user-locales)

### Steps to Reproduce

1. open system settings -> 'language and region' and change 'formats' to a different language and hit 'set language' (the 2nd button)
2. logout and log in again
3. open epiphany and try to open any website

### Expected Behavior

Epiphany won't load any website. It's very inconvenient to explain to a new user why this seems to be a problem. According to the answer provided on StackExchange there is already a fix available: https://github.com/flatpak/flatpak/issues/3712

### OS Version

6.x (Odin)

### Software Version

Latest release (I have run all updates)

### Log Output

```
jul 18 20:54:55 ASUS-FLOBOOK io.elementary.wingpanel.desktop[15636]: flatpak-spawn: Invalid byte sequence in conversion input
jul 18 20:54:55 ASUS-FLOBOOK io.elementary.wingpanel.desktop[15636]: Try "flatpak-spawn --help" for more information.
jul 18 20:54:55 ASUS-FLOBOOK epiphany[6253]: Web process crashed
```

### Hardware Info

_No response_