feat: change the behavior of schema KeyKubeconfigPath

[naka-gawa]

Hi, Thank you always!

The suggestion for this PR is to allow the user to control the path of kubeconfig.

"Kubeconfig_path" is defined as an optional parameter By default, "kubeconfig" is generated in the tmp area. Also, if i want to inherit "kubeconfig" in another environment, i set the parameter "kubeconfig_path". (Example: CI)

default setting 'kubeconfig_path is null'

• terraform.tf

  resource "eksctl_cluster" "blue" {
  eksctl_bin  = "eksctl"
  name        = "sandbox-tmnakagawa-1"
  region      = "ap-northeast-1"
  api_version = "eksctl.io/v1alpha5"
  version     = "1.14"
  vpc_id      = data.terraform_remote_state.vpc.outputs.vpc_id
  revision    = 1
  spec = <<EOS
  -snip-

• terraform output

  Apply complete! Resources: 2 added, 0 changed, 0 destroyed.
  Outputs:
  azs = [
  "ap-northeast-1a",
  "ap-northeast-1c",
  "ap-northeast-1d",
  ]
  caller_id = 167855287371
  kubeconfig_path_blue = /var/folders/8g/cj5brb115g1369knxjwyb_351xk4ng/T/tf-eksctl-kubeconfig482863336
  region = ap-northeast-1
  user_id = infra

add setting "kubeconfig_path"

• terraform.tf

  resource "eksctl_cluster" "blue" {
  eksctl_bin  = "eksctl"
  name        = "sandbox-tmnakagawa-1"
  region      = "ap-northeast-1"
  api_version = "eksctl.io/v1alpha5"
  version     = "1.14"
  vpc_id      = data.terraform_remote_state.vpc.outputs.vpc_id
  kubeconfig_path = "kubeconfig/sandbox-tmnakagawa-1" <<< here!!
  revision    = 1
  spec = <<EOS
  -snip-

• terraform output

  Apply complete! Resources: 1 added, 0 changed, 0 destroyed.
  Outputs:
  azs = [
  "ap-northeast-1a",
  "ap-northeast-1c",
  "ap-northeast-1d",
  ]
  caller_id = 167855287371
  kubeconfig_path_blue = kubeconfig/sandbox-tmnakagawa-1 <<< here!!
  region = ap-northeast-1
  user_id = infra