Refactoring installFromFS from notation CLI to notation-go

Originally posted by @shizhMSFT in #827 (comment)

Created issue to track.

Closing this issue as we have discussed this again. The reason to close is that:
Even if we move the fs.FS logic, such as zip related functions, to notation-go, we still have to have a tmp dir to unzip before the installation. This is because get-plugin-metadata requires os path to execute. Golang's io/fs does not provide os path information during WalkDir.
/cc: @shizhMSFT