[wasm][debugger] Fix expression evaluation when it is a reference (#41135)

[wasm][debugger] Fix expression evaluation when it is a reference (#41135)

* [wasm][debugger] Fix expression evaluation when it is a reference

.. preceded by spaces. Eg: `"  foo.dateTime", or `"  foo.count"`

* Explanation of the fix:

- these particular expressions end up in the code path where we get a
SimpleMemberAccessExpression, and only one member access (like `a.b.c`)
was found.

- that code path had
    `return memberAccessValues[0]?["value"]?.Value<JObject>();`

  - which is incorrect, and we need to return `memberAccessValues[0]`,
  which is the value itself.