Fix proxy usage when *_PROXY are present in environment (#7309)

Since a790935d02 all proxy users
should be properly configured

Now when you have *_PROXY vars in your environment it can leads to failure
if NO_PROXY is not correct, or to persistent configuration changes
as seen with kubeadm in 1c5391dda7

Instead of playing constant whack-a-bug, inject empty *_PROXY vars everywhere
at the play level, and override at the task level when needed

Signed-off-by: Etienne Champetier <e.champetier@ateme.com>
(cherry picked from commit 067db686f6)

roles/kubernetes/master/tasks/kubeadm-setup.yml

@@ -156,7 +156,8 @@
   until: kubeadm_init is succeeded or "field is immutable" in kubeadm_init.stderr
   when: inventory_hostname == groups['kube-master']|first and not kubeadm_already_run.stat.exists
   failed_when: kubeadm_init.rc != 0 and "field is immutable" not in kubeadm_init.stderr
-  environment: '{{ proxy_disable_env | combine({"PATH": "{{ bin_dir }}:{{ ansible_env.PATH }}"}) }}'
+  environment:
+    PATH: "{{ bin_dir }}:{{ ansible_env.PATH }}"
   notify: Master | restart kubelet
 
 - name: set kubeadm certificate key
@@ -171,7 +172,6 @@
   shell: >-
     {{ bin_dir }}/kubeadm --kubeconfig /etc/kubernetes/admin.conf token delete {{ kubeadm_token }} || :;
     {{ bin_dir }}/kubeadm --kubeconfig /etc/kubernetes/admin.conf token create {{ kubeadm_token }}
-  environment: "{{ proxy_disable_env }}"
   changed_when: false
   when:
     - inventory_hostname == groups['kube-master']|first
@@ -182,7 +182,6 @@
 
 - name: Create kubeadm token for joining nodes with 24h expiration (default)
   command: "{{ bin_dir }}/kubeadm --kubeconfig /etc/kubernetes/admin.conf token create"
-  environment: "{{ proxy_disable_env }}"
   changed_when: false
   register: temp_token
   retries: 5