Only setup *_PROXY env variables where needed (#7095)

no_proxy is a pain to get right, and having proxy variables present causes issues
(k8s components get proxy configuration after upgrade, see #7100)

It's better to only configure what require proxy:
- the runtime (containerd/docker/crio)
- the package manager + apt_key
- the download tasks

Tested with the following clusters
- 4 CentOS 8 nodes
- 1 Ubuntu 20.04 node

Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

roles/bootstrap-os/tasks/bootstrap-debian.yml

@@ -8,7 +8,6 @@
   changed_when: false
   # This command should always run, even in check mode
   check_mode: false
-  environment: {}
   tags:
     - facts
 
@@ -19,12 +18,10 @@
   changed_when: false
   # This command should always run, even in check mode
   check_mode: false
-  environment: {}
 
 - name: Add http_proxy to /etc/apt/apt.conf if http_proxy is defined
   raw: echo 'Acquire::http::proxy "{{ http_proxy }}";' >> /etc/apt/apt.conf
   become: true
-  environment: {}
   when:
     - http_proxy is defined
     - need_http_proxy.rc != 0
@@ -37,12 +34,10 @@
   changed_when: false
   # This command should always run, even in check mode
   check_mode: false
-  environment: {}
 
 - name: Add https_proxy to /etc/apt/apt.conf if https_proxy is defined
   raw: echo 'Acquire::https::proxy "{{ https_proxy }}";' >> /etc/apt/apt.conf
   become: true
-  environment: {}
   when:
     - https_proxy is defined
     - need_https_proxy.rc != 0
@@ -55,14 +50,12 @@
   changed_when: false
   # This command should always run, even in check mode
   check_mode: false
-  environment: {}
   when:
     - '"bionic" in os_release.stdout'
 
 - name: Change Network Name Resolution configuration
   raw: sed -i 's/^DNSSEC=yes/DNSSEC=allow-downgrade/g' /etc/systemd/resolved.conf
   become: true
-  environment: {}
   when:
     - '"bionic" in os_release.stdout'
     - need_dnssec_allow_downgrade.rc
@@ -70,7 +63,6 @@
 - name: Restart systemd-resolved service
   raw: systemctl restart systemd-resolved
   become: true
-  environment: {}
   when:
     - '"bionic" in os_release.stdout'
     - need_dnssec_allow_downgrade.rc
@@ -80,7 +72,6 @@
     apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y python3-minimal
   become: true
-  environment: {}
   when:
     - need_bootstrap.rc != 0