Allow `oc cp` to Copy a Single File to a Directory

[thekief]

Tools similar to oc, such as adb, that allow to copy file from a remote, offer to copy single file without needing to specify a destination and allow to, e.g. just provide a target directory, such as ..

It would be a nice quality-of-life improvement to have something similar implemented.

Version

Client Version: 4.17.5
Kustomize Version: v5.0.4-0.20230601165947-6ce0bf390ce3
Kubernetes Version: v1.27.15+6147456

Steps To Reproduce

1. execute oc cp <pod name>:<path to a single file> .

Current Result

tar: Removing leading `/' from member names
error: open .: is a directory

Expected Result

The file is copied to the current directory.

Additional Information

n/a