Remove version text from distribution tarball file name.

The distribution tarball file name currently includes the app's version, e.g., perfspect_3.0.0.tgz. Thus, the file name will change with every release. By removing the version from the file name, we can more easily provide a URL that can me remain the same across releases, e.g., https://github.com/intel/PerfSpect/releases/latest/download/perfspect.tgz.