Different script handling from standard runner breaks some scripts

[Burstaholic]

From the GitLab CI Project Settings page:

All lines will be concatenated in one file and executed. 
If you change the working directory or the environment in one line - it will affect the next lines too

Since the Windows runner executes each command in a new shell, this guarantee is broken, making complex build scripts rather more difficult to use.

[lkm]

@Burstaholic I came across similar difficulties. I was messing with implementing Powershell instead of cmd, because output colours weren't showing up thus making msbuild output rather tedious to look at for larger solutions. However, it seems very hard then to check execution success because error codes are inconsistent on Windows (see http://stackoverflow.com/a/9949909), which is presumable why the decision to run every line separately was made.