Ignore glob matches which are not directories containing a package.json

[i-like-robots]

🤦‍♂️

The glob match will find both files and folders which Athloi has until now not checked. I have updated this so that it checks two things:

1. That the glob match is a directory and not a file
2. That a package manifest exists at that path and throw and clear error if it does not

Example error from previous behaviour:

✖ Task failed: "Cannot find module '/Users/matt.hinchliffe/Projects/anvil/examples/readme.md/package.json'"

🐿 v2.10.0