CI: Specify ANSIBLE_STRATEGY in tasks that run ansible or ansible-playbook

This makes the behaviour more consistent across jobs that run with
`mitogen_linear` or plain `linear`.

tests/ansible/integration/connection/disconnect_during_module.yml

@@ -13,6 +13,7 @@
     vars:
       ansible_python_interpreter: "{{ ansible_playbook_python }}"
     environment:
+      ANSIBLE_STRATEGY:  "{{ lookup('env', 'ANSIBLE_STRATEGY') | mandatory }}"
       ANSIBLE_VERBOSITY: "{{ ansible_verbosity }}"
     command: |
       ansible-playbook

tests/ansible/integration/runner/missing_module.yml

@@ -5,6 +5,7 @@
     - name: Run missing_module
       connection: local
       environment:
+        ANSIBLE_STRATEGY:  "{{ lookup('env', 'ANSIBLE_STRATEGY') | mandatory }}"
         ANSIBLE_VERBOSITY: "{{ ansible_verbosity }}"
       vars:
         ansible_python_interpreter: "{{ ansible_playbook_python }}"

tests/ansible/integration/ssh/timeouts.yml

@@ -14,6 +14,7 @@
       connection: local
       environment:
         ANSIBLE_SSH_TIMEOUT: 10
+        ANSIBLE_STRATEGY:  "{{ lookup('env', 'ANSIBLE_STRATEGY') | mandatory }}"
         ANSIBLE_VERBOSITY: "{{ ansible_verbosity }}"
       vars:
         ansible_python_interpreter: "{{ ansible_playbook_python }}"

tests/ansible/integration/stub_connections/setns_lxc.yml

@@ -15,6 +15,7 @@
 
     - name: Run stub-lxc-info.py
       environment:
+        ANSIBLE_STRATEGY:  "{{ lookup('env', 'ANSIBLE_STRATEGY') | mandatory }}"
         ANSIBLE_VERBOSITY: "{{ ansible_verbosity }}"
       command: |
         sudo -nE "{{lookup('env', 'VIRTUAL_ENV')}}/bin/ansible"

tests/ansible/integration/stub_connections/setns_lxd.yml

@@ -15,6 +15,7 @@
 
     - name: Run ansible stub-lxc.py
       environment:
+        ANSIBLE_STRATEGY:  "{{ lookup('env', 'ANSIBLE_STRATEGY') | mandatory }}"
         ANSIBLE_VERBOSITY: "{{ ansible_verbosity }}"
       command: |
         sudo -nE "{{lookup('env', 'VIRTUAL_ENV')}}/bin/ansible"

tests/ansible/regression/become_test.yml

@@ -2,7 +2,6 @@
   hosts: test-targets:&linux_containers
   become: true
   become_user: mitogen__pw_required
-  strategy: mitogen_linear
   tasks:
     - command: whoami
       changed_when: false

tests/ansible/regression/issue_1087__template_streamerror.yml

@@ -20,6 +20,7 @@
           vars:
             ansible_python_interpreter: "{{ ansible_playbook_python }}"
           environment:
+            ANSIBLE_STRATEGY:  "{{ lookup('env', 'ANSIBLE_STRATEGY') | mandatory }}"
             ANSIBLE_VERBOSITY: "{{ ansible_verbosity }}"
           command:
             cmd: >

tests/ansible/regression/issue_952__ask_become_pass.yml

@@ -9,6 +9,7 @@
       vars:
         ansible_python_interpreter: "{{ ansible_playbook_python }}"
       environment:
+        ANSIBLE_STRATEGY:  "{{ lookup('env', 'ANSIBLE_STRATEGY') | mandatory }}"
         ANSIBLE_VERBOSITY: "{{ ansible_verbosity }}"
       expect:
         command: >