Although you may be able to do that, there is no reason for it with anonymous git checkout and pulls. The development environment contains everything that you need for retrieving, updating and compiling the source. Not sure what the "sourcetree terminal" exactly is, but if you have downloaded the development environment you don't need it.
No that is correct, you don't need SourceTree (a program which works on windows for downloading sources) and not wanting to sound enigmatic at all, or cause more confusion, what I meant with the "Sourcetree Terminal" is simply this command line interface in Sourcetree you can use to type the different commands to retrieve the source. I stumbled on the post with the development package after I downloaded the source with Sourcetree. That is why I used that to get the source on my pc and it was only later that I discovered the thread you mentioned A_C.
Anyway, the "Sourcetree" terminal window is shown in the screenshot below, and is the one I used to retrieve the source. It is the same as the "git shell", so you cannot compile the source in this terminal window, you will need Msys.bat terminal to do that.
Alpha Backer of Elite Dangerous
With 250 GBP