LDC: remove the dlang version number
LDC: remove the dlang version number

This reduces the length of the compiler name to a manageable size.
dkm/gcc-explorer,mattgodbolt/gcc-explorer,ibuclaw/gcc-explorer,mattgodbolt/gcc-explorer,dkm/gcc-explorer,mattgodbolt/compiler-explorer,ibuclaw/gcc-explorer,dkm/gcc-explorer,mattgodbolt/compiler-explorer,ibuclaw/gcc-explorer,mattgodbolt/compiler-explorer,dkm/gcc-explorer,ibuclaw/gcc-explorer,mattgodbolt/compiler-explorer,ibuclaw/gcc-explorer,dkm/gcc-explorer,mattgodbolt/gcc-explorer,mattgodbolt/compiler-explorer,mattgodbolt/compiler-explorer,mattgodbolt/compiler-explorer,mattgodbolt/gcc-explorer,dkm/gcc-explorer,dkm/gcc-explorer,dkm/gcc-explorer,mattgodbolt/compiler-explorer,mattgodbolt/gcc-explorer,dkm/gcc-explorer