[Fix] Escape backslashes in PowerShell ArgumentList

[CommandMC]

Backslashes are mostly fine to just include without escaping, but there are certain cases where they can cause issues. One of those would be when specifying just a drive letter (X:\) as one argument (for example as the install path for a game). In that case, when adding the necessary escape characters around the argument, we'd end up with "`"X:\`"". PS would then see that the backtick is escaped by a \ (even though it's not supposed to be), and the whole thing would fall apart

Resolving this is luckily rather easy, we can simply replace every one \ with two \ to end up with one escaped \, which can then no longer break anything around it

To test:

• Be on Windows
• Try to install a game onto a "bare" drive letter (for example D:\)
• Won't work on main, will work here

This still needs a bit more testing with uncommon arguments, PS is pretty unpredictable after all

---

Use the following Checklist if you have changed something on the Backend or Frontend:

• Tested the feature and it's working on a current and clean install.
• Tested the main App features and they are still working on a current and clean install. (Login, Install, Play, Uninstall, Move games, etc.)
• Created / Updated Tests (If necessary)
• Created / Updated documentation (If necessary)

[flavioislima]

Tested here and works fine. Nice job!