Fixed dangling symlinks in builds

[UebelAndre]

In some cases, the assumed output for a build, lib*.so, is actually a symlink which points to lib*.#.#.#.so. This results in issues like

ERROR: /home/user/.cache/bazel/_bazel_user/3821989c4a000f3a0c8be3e30c90c4f7/external/libjpeg_turbo/BUILD.bazel:23:6: output 'external/libjpeg_turbo/libjpeg_turbo/lib/libjpeg.so' is a dangling symbolic link

To fix this, any explicitly requested output should be resolved to it's full file.

[jsharpe]

+1 as this fixes the dangling symlinks for the specified outputs but we still have #449 to think about how to handle properly - its not ideal that we end up with copies of shared libraries which should be symlinks. ldconfig complains about the fact that the .so library isn't a symlink.

I've not checked but do we also have broken symlinks in the gen_dir output too?

[UebelAndre]

+1 as this fixes the dangling symlinks for the specified outputs but we still have #449 to think about how to handle properly - its not ideal that we end up with copies of shared libraries which should be symlinks. ldconfig complains about the fact that the .so library isn't a symlink.

I've not checked but do we also have broken symlinks in the gen_dir output too?

Yeah, this would have been an existing issue from before #575

This change restores previous behavior but is still incorrect but incorrect for functionality that didn't work or was undefined previously.