[archive] Print stderr if the gpg command fails

[jcastill]

Since stderr is now captured in sos_get_command_output() this commit enables it for the _encrypt() function and prints the error received if the gpg command failed.

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[packit-as-a-service]

Congratulations! One of the builds has completed. 🍾

You can install the built RPMs by following these steps:

• sudo yum install -y dnf-plugins-core on RHEL 8
• sudo dnf install -y dnf-plugins-core on Fedora
• dnf copr enable packit/sosreport-sos-4032
• And now you can install the packages.

Please note that the RPMs should be used only in a testing environment.

[pmoravec]

Why not. While I think the gpg feature is almost never used (at least I havent seen it to be used, at least).