Querying in REPL is broken in 1.4 (undue unbound identifier error)

[yannham]

Describe the bug
It seems that since 1.4, trying to query a value introduced during a REPL session with a top-level let unduly raises an unbound identifier error, although the identifier is bound. Evaluation isn't impacted, it's just querying.

To Reproduce

Start a REPL session and:

nickel> let foo = 1
nickel> :query foo
error: unbound identifier `foo`
  ┌─ <repl-query>:1:1
  │
1 │ foo
  │ ^^^ this identifier is unbound

Expected behavior
I expect the query to succeed and just return nothing in this case.

Additional context
The cause has been found already and a fix is on the way. This issue is just to make it searchable and for the record.