Fix CSE bugs

[adambarreiro]

Overview

This PR fixes two bugs in vcd_cse_kubernetes_cluster:

Closes #1265

When any user performs a change in a vcd_cse_kubernetes_cluster and runs terraform plan, the output will always show the Kubeconfig, which can be used to access the cluster by unauthorized people.

Closes #1258

When a user tries to create a vcd_cse_kubernetes_cluster with a network that belongs to a VDC Group, cluster creation fails as the network can't be found.

Fix

• This PR adds Sensitive: true to the kubeconfig attribute.
• This PR bumps Go SDK so the VDC Group networks can be found. Fix is Fix CSE cluster creation when using VDC Groups go-vcloud-director#674

Extra changes

During the implementation of vcd_cse_kubernetes_cluster in previous release, I added some redundant validation functions that were already implemented in the validation package. I've removed these functions and just used the available ones, to reduce boilerplate code.

The removed functions are matchRegex and minimumValue, replaced by validation. StringMatch and validation.IntAtLeast, respectively.

Test

Tests passed in VCD 10.5.1 with CSE 4.2.1.

To test the fix about VDC Groups, one can create an extra VDC in their CSE environment, create a VDC Group, increase the scope of the existing Edge Gateway, then the cluster creation with the routed network should not fail anymore:

data "vcd_vdc_group" "group" {
  org  = "tenant_org"
  name = "group" # An ad-hoc VDC group created for this manual check
}

data "vcd_nsxt_edgegateway" "egw" {
  org      = data.vcd_org_vdc.vdc.org
  owner_id = data.vcd_vdc_group.group.id # References the VDC group, not VDC
  name     = "tenant_edgegateway"
}

data "vcd_network_routed_v2" "routed" {
  org             = data.vcd_nsxt_edgegateway.egw.org
  edge_gateway_id = data.vcd_nsxt_edgegateway.egw.id
  name            = "tenant_net_routed"
}