Ensure kubeadm doesn't use proxy (#7275)

* Move proxy_env to kubespray-defaults/defaults

There is no reasons to use set_facts here

Signed-off-by: Etienne Champetier <e.champetier@ateme.com>

* Ensure kubeadm doesn't use proxy

*_proxy variables might be present in the environment (/etc/environment, bash profile, ...)
When this is the case we end up with those proxy configuration in /etc/kubernetes/manifests/kube-*.yaml manifests

We cannot unset env variables, but kubeadm is nice enough to ignore empty vars
93d288e2a4/cmd/kubeadm/app/util/env.go (L27)

Signed-off-by: Etienne Champetier <e.champetier@ateme.com>

roles/kubernetes/control-plane/tasks/kubeadm-secondary.yml

@@ -16,6 +16,7 @@
     --config {{ kube_config_dir }}/kubeadm-config.yaml
     upload-certs
     --upload-certs
+  environment: "{{ proxy_disable_env }}"
   register: kubeadm_upload_cert
   when:
     - inventory_hostname == groups['kube-master']|first
@@ -57,6 +58,7 @@
     {{ bin_dir }}/kubeadm join
     --config {{ kube_config_dir }}/kubeadm-controlplane.yaml
     --ignore-preflight-errors=all
+  environment: '{{ proxy_disable_env | combine({"PATH": "{{ bin_dir }}:{{ ansible_env.PATH }}"}) }}'
   register: kubeadm_join_control_plane
   retries: 3
   throttle: 1
@@ -64,8 +66,6 @@
   when:
     - inventory_hostname != groups['kube-master']|first
     - kubeadm_already_run is not defined or not kubeadm_already_run.stat.exists
-  environment:
-    PATH: "{{ bin_dir }}:{{ ansible_env.PATH }}"
 
 - name: Set secret_changed to false to avoid extra token rotation
   set_fact: