Upgrade to 4.1.1 upstream version. This is an incompatible upgrade, following EPEL policy.

• Some functionality previously provided by the singularity remote command is split into new singularity registry and singularity keyserver commands.
• The singularity remote add command now sets a newly added remote as the default (unless suppressed).
• The --vm flag to start singularity inside a Virtual Machine has been removed.
• Bind mounts are now performed in the order in which they are specified.
• Current working directory on the host is now created in the container, restoring a behaviour from Singularity <3.6.0.
• If the current directory paths on the container and host contains symlinks to different locations, the current working directory is not mounted.