Adding "tag_ids" when creating a card doesn't attach a tag on the card.

[AndrijaSkontra]

Steps to Reproduce:
I am sending a POST request to the /cards endpoint with a valid tag ID:

curl -X POST "https://app.fizzy.do/<my-slug>/boards/<my-board-id>/cards" \
-H "Authorization: Bearer xxxxx" \
-H "Content-Type: application/json" \
-d '{
  "card": {
    "title": "Some title",
    "tag_ids": ["<tag-id>"]
  }
}'

Expected Result:
The response should return the card object with the specified tag included in the "tags" array.

Actual Result:
The card is created, but the "tags" array is empty:

{
  "id": "03fwvxnl0lkkq35c9vq03bscr",
  "title": "Some title",
  "tags": [],  // <--- Should contain the tag associated with the tag_id
  ...
}

Is anyone else experiencing this, or is there a different parameter name I should be using for tags?

[flavorjones]

Pinging @robzolkos who's been working on the API.

[robzolkos]

Tracking the fix in #2830