screen: depend on libxcrypt

[pyrmont]

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Summary

To fix a problem on Linux loading the libcrypt shared library, this PR introduces a dependency on Linux on libxcrypt. This is the same solution as in #108663.

Background

I am running the following:

Operating System: Debian GNU/Linux 11 (bullseye)  
          Kernel: Linux 5.10.0-18-amd64
    Architecture: x86-64

After installing GNU Screen, I see the following error when trying to run screen:

screen: error while loading shared libraries: libcrypt.so.1: cannot open shared object file: No such file or directory

I believe this is a result of changes to glibc that removed libcrypt (see here, here and here). Adding a dependency on libxcrypt solves the problem.

[danielnachun]

Thanks for this fix. I guess this was unnoticed before because screen must not have been tested in CI for a long time.

[BrewTestBot]

🤖 A scheduled task has triggered a merge.

[pyrmont]

@danielnachun No worries. I imagine most people who are on Linux would be using tmux ;) Thanks for merging it in so quickly!