fix variable enums value empty string

[baonguyen212002]

Describe the bug

Expected behavior/Solution

Steps to reproduce

 type Query {
    userAttendanceStatistics(
        dateRange: DateRange @whereBetween
        userId: ID @where
        blockType: AttendanceBlockType @convertEmptyStringsToNull
    ): [UserAttendanceStatistics]
}

query userAttendanceStatistics($dateRange: DateRange, $userId: ID, $blockType: AttendanceBlockType) {
  userAttendanceStatistics(
    dateRange: $dateRange
    userId: $userId
    blockType: $blockType
  ) {
    user {
      id
      name
      avatar
      position
      name
      nickname
      email
      phone
      __typename
    }
    checkin
    checkout
    totalWorkingHours
    status
    __typename
  }
}

{
  "dateRange": {
    "from": "2024-10-25",
    "to": "2024-10-25"
  },
  "userId": "9",
  "blockType": ""
}

Output/Logs

{
  "errors": [
    {
      "message": "Variable \"$blockType\" got invalid value (empty string); Expected type AttendanceBlockType.",
      "extensions": {
        "category": "graphql"
      },
      "locations": [
        {
          "line": 1,
          "column": 68
        }
      ]
    }
  ]
}

Click to expand

# Add in log output/error messages here

Lighthouse Version

[spawnia]

Duplicate of #2625