Setting '*_key_prefix' variables to empty string results in S3 paths containing pointless duplicit slash "/"

[marko-fabry]

Describe the bug

Setting '*_s3_key_prefix' variables to empty string results in S3 paths containing pointless duplicit slash "/"

Versions

• Terraform: 1.4.6
• Provider: 5.0
• Module: v2.1.0

Reproduction

The following is from the simple example + *_key_prefix variables set to empty string.

module "secure_baseline" {
  source = "nozaq/secure-baseline/aws""

  audit_log_bucket_name           = "test-test-test-audit-log-bucket"
  aws_account_id                  = data.aws_caller_identity.current.account_id
  region                          = var.region
  support_iam_role_principal_arns = []


  audit_log_bucket_force_destroy = true

  cloudtrail_s3_key_prefix    = ""
  config_s3_bucket_key_prefix = ""
  vpc_flow_logs_s3_key_prefix = ""

  providers = {
    aws                = aws
    aws.ap-northeast-1 = aws.ap-northeast-1
    aws.ap-northeast-2 = aws.ap-northeast-2
    aws.ap-northeast-3 = aws.ap-northeast-3
    aws.ap-south-1     = aws.ap-south-1
    aws.ap-southeast-1 = aws.ap-southeast-1
    aws.ap-southeast-2 = aws.ap-southeast-2
    aws.ca-central-1   = aws.ca-central-1
    aws.eu-central-1   = aws.eu-central-1
    aws.eu-north-1     = aws.eu-north-1
    aws.eu-west-1      = aws.eu-west-1
    aws.eu-west-2      = aws.eu-west-2
    aws.eu-west-3      = aws.eu-west-3
    aws.sa-east-1      = aws.sa-east-1
    aws.us-east-1      = aws.us-east-1
    aws.us-east-2      = aws.us-east-2
    aws.us-west-1      = aws.us-west-1
    aws.us-west-2      = aws.us-west-2
  }
}

Expected behavior

The S3 destination paths don't contain double "/".

Actual behavior

The S3 destination paths contain double "/" after the S3 bucket name.

Additional context

I'll submit PR for this.