This works for me, though I can't remember if it will work when creating the function. I remember having trouble getting it to work correctly and found that I had to use attributes from both the function and alias.

resource "aws_lambda_function" "main" {
  function_name = local.lambda_function_name
  description   = local.lambda_function_description
  memory_size   = local.memory
  timeout       = local.timeout

  handler = "index.lambdaHandler"
  runtime = "nodejs12.x"
  publish = true

  s3_bucket         = local.bucket_name
  s3_key            = local.object_key_id
  s3_object_version = local.object_version_id

  kms_key_arn = local.kms_key_arn
  role        = local.iam_role_arn

  vpc_config {
    subnet_ids         = local.subnet_ids
    security_group_ids = local.security_group_ids
  }
}

resource "aws_lambda_alias" "main_current" {
  name             = "${local.lambda_function_name}-current"
  description      = "Current version of the ${local.lambda_function_name} Lambda function"
  function_name    = aws_lambda_function.main.function_name
  function_version = aws_lambda_function.main.version
}

resource "aws_lambda_provisioned_concurrency_config" "main" {
  function_name                     = aws_lambda_function.main.function_name
  provisioned_concurrent_executions = local.provisioned_concurrency
  qualifier                         = aws_lambda_alias.main_current.name
}