Update AddingALibrary.md
Update AddingALibrary.md

As suggested by @toughengineer in #2772
mattgodbolt/compiler-explorer,mattgodbolt/compiler-explorer,mattgodbolt/compiler-explorer,mattgodbolt/compiler-explorer,mattgodbolt/compiler-explorer,mattgodbolt/compiler-explorer,mattgodbolt/compiler-explorer,mattgodbolt/compiler-explorer