Normalizer interprets "expression" as a MBQL :expression, but it is just a column name

[luizarakaki]

Describe the bug

Customer is getting this exception:

{
  "via": [
    {
      "type": "clojure.lang.ExceptionInfo",
      "message": "Error normalizing query: Error normalizing form: null",
      "data": {
        "query": [
          "expression",
          null,
          "sum",
          "sum_3",
          "sum_2"
        ],
...

When trying to GET /api/cards
with this card

{"table.pivot_column" "created_month",
 "table.cell_column" "sum",
 "card.title" "Funnel view by month",
 "table.column_formatting"
 [{"columns" ["expression" nil "sum" "sum_3" "sum_2"],
...

https://metaboat.slack.com/archives/C04DN5VRQM6/p1716477256872509

To Reproduce

See logs above

Expected behavior

1. It shouldn't try to normalize columns
2. The GET request shouldn't completely fail. It should remove the erroring question and warn the user

Logs

No response

Information about your Metabase installation

- Cloud instance, latest v49

Severity

P1

Additional context

https://metaboat.slack.com/archives/C04DN5VRQM6/p1716477256872509