zip file must be unpacked with jar rather than tar

[philwalk]

Version(s)

# scala-cli version
Scala CLI version: 1.3.1
Scala version (default): 3.4.1

Describe the bug
The Windows instructions for manually installing scala-cli incorrectly specify tar rather than jar command line for unpacking a zip file.

To Reproduce

# tar -xf ~/scala-cli.zip
tar: This does not look like a tar archive
tar: Skipping to next header
tar: Exiting with failure status due to previous errors

# jar -xf scala-cli.zip

Expected behaviour
This is a simple typo, but can result in a confusing experience for novice users.
I will submit a PR with the fix.