* Filter out empty glob patterns
An empty argument to the "glob" command will now produce an empty result.
Working towards nushell/nushell#6653.
* Run `cargo fmt --all`
Just autoformatted the repo so that CI passes and we have a consistent code
format across modules.
* Treat empty glob argument as error
The glob command will now report an empty string argument as an error instead
of silently ignoring it.
See https://github.com/nushell/nushell/pull/6707#discussion_r993345013.
* Add tests for glob command
Two small tests for the glob command, one to check that the empty string errors
it, and another to sanity check the '*' glob, have been added.
* Rename glob sanity check star test
Co-authored-by: Kyle Anderson <kyle.anderson@uwaterloo.ca>