doc: Windows + clang/ninja build guide format cleanup

[jsjtxietian]

The current doc about building with clang and ninja on windows contains a minor formatting issue, this pr improves this part's readability.

See the current version:

Should be more clear now:

[ehoogeveen-medweb]

To ensure that paths containing whitespace are correctly preserved with set, you probably want to wrap the whole thing in double quotes:

set "LIB=C:\Program Files (x86)\Windows Kits\10\Lib\10.0.22621.0\um\x64;C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.41.34120\lib\x64\uwp;C:\Program Files (x86)\Windows Kits\10\Lib\10.0.22621.0\ucrt\x64"

Though note that set is only for the current session. To set the environment variable permanently you'd need setx:

setx LIB "C:\Program Files (x86)\Windows Kits\10\Lib\10.0.22621.0\um\x64;C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.41.34120\lib\x64\uwp;C:\Program Files (x86)\Windows Kits\10\Lib\10.0.22621.0\ucrt\x64"

[jsjtxietian]

To ensure that paths containing whitespace are correctly preserved with set, you probably want to wrap the whole thing in double quotes:

set "LIB=C:\Program Files (x86)\Windows Kits\10\Lib\10.0.22621.0\um\x64;C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.41.34120\lib\x64\uwp;C:\Program Files (x86)\Windows Kits\10\Lib\10.0.22621.0\ucrt\x64"

I agree although the version without double quotes works too in developer Command Prompt For VS. I only addressed format issue in this PR, did not touch the content. cc @Srihari-mcw