A few `basic` tests failing

[anatoly-scherbakov]

Comments test

Expand operation converts a mapping with a # in key to an empty object. Try this out in the playground:

{
  "@context": {
    "@vocab": "http://example.com/"
  },
  "@id": "http://example.org/test#example",
  "@type": "t1",
  "notacomment": [
    {"this is#not": "a comment"}
  ]
}