Invalid json file when enabling Google Play integration

Hi, I’m trying to use the Google Play integration to connect my self hosted Gitlab instance to the Play Store, but when I upload the json file, I’m always getting the following error message:

How I created the JSON file:

  1. Go to https://console.cloud.google.com/iam-admin/serviceaccounts
  2. Click Create Service Account, give it a name and create the account
  3. Click on the 3 dots on the right site of the service account and choose “Manage keys”
  4. Click on “Create new key” and choose “JSON”
  5. The json is being downloaded
  6. Upload the json file to Gitlab
  7. Gitlab rejects the json file and says Error: The file you're trying to upload is not a service account key.

I opened the json file and it has the following structure:

{
  "type": "service_account",
  "project_id": "my-project-1234",
  "private_key_id": "<removed>",
  "private_key": "<removed>",
  "client_email": "some-mail@some-project-1234.iam.gserviceaccount.com",
  "client_id": "123456789012345678901234567890",
  "auth_uri": "https://accounts.google.com/o/oauth2/auth",
  "token_uri": "https://oauth2.googleapis.com/token",
  "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
  "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/test-<removed>",
  "universe_domain": "googleapis.com"
}

Is that the correct file I need or what I’m doing wrong here?