Docs, StS: Document setup for Slay the Spire GOG/Game Pass installations

[remyjette]

What is this fixing or adding?

Adds instructions for setting up Slay the Spire using an Xbox Game Pass installation as opposed to Steam

How was this tested?

I went through the steps locally and everything works, both starting a game and sending/receiving items.

If this makes graphical changes, please attach screenshots.

This is what the doc looks like when rendered in the website:

[KonoTyran]

I'm not a fan of telling the user to just double click on the mod the spire jar file as that will use whatever Java version they may or may not have installed, wich could cause some issues due to version differences, I would perfer including a bat/sh file that would use the bundled version of the jre that comes with StS, on steam this is inside of a jre folder in the sts install directory.

[remyjette]

I'm not a fan of telling the user to just double click on the mod the spire jar file as that will use whatever Java version they may or may not have installed, wich could cause some issues due to version differences, I would perfer including a bat/sh file that would use the bundled version of the jre that comes with StS, on steam this is inside of a jre folder in the sts install directory.

My understanding is ModTheSpire.jar will swap to the local StS JRE even if you originally launched it with a different JRE

for example

D:\XboxGames\Slay The Spire\Content>"C:\Program Files (x86)\Common Files\Oracle\Java\javapath\java.exe" -jar ModTheSpire.jar
Searching for Workshop items...
Using local StS JRE @ D:\XboxGames\Slay The Spire\Content\jre\bin\java.exe

With that being said I'm going to change it anyway. Double-clicking ModTheSpire.jar isn't ideal because even if it would swap to the bundled JRE that isn't a good experience for anyone who doesn't have Java in their PATH.