bst show expands '*' to artifact refs

Summary

If you try bst show '*', then you will be presented with an error like:

Cannot perform this operation with artifact refs:

    running-commands/hello/8276376b077eda104c812e6ec2f488c7c9eea211ce572c83d734c10bf241209f
    running-commands/hello/5c4ed6545bfab8fde4a19fe01e8b1d5534ad3f5419f3c17eb558109c86432cea

If you try instead with bst show '*.bst' then you get what you might expect:

      cached d23ade23cf21ef256f1b1c6c7e25af5d0a69346cacb38a411d1eeed279f548da alpine.bst
      cached eaa9ad447253da4a89215c783b73d68de8e62212174d81d04ccc7e6dcc088dde base.bst
      cached 8276376b077eda104c812e6ec2f488c7c9eea211ce572c83d734c10bf241209f hello.bst

The artifact refs are invalid input for bst show, as such we should not have the CLI expand wildcards to existing artifact refs for this command.