tests: Check Mitogen+Ansible discovered interpreter fresh Ansible result

Previously this test used a manually compiled list of results, which is
fragile and an ongoing maintenance burden. New method should 'just work' and
be more transparent.

This technique might be more widely applicable in the test suite.

tests/ansible/integration/interpreter_discovery/ansible_2_8_tests.yml

@@ -1,58 +1,20 @@
 # ripped and ported from https://github.com/ansible/ansible/pull/50163/files, when interpreter discovery was added to ansible
 ---
+- name: integration/interpreter_discovery/ansible_2_8_tests.yml, baseline
+  hosts: test-targets
+  strategy: linear
+  tasks:
+    - meta: clear_facts
+    - name: Discover interpreter, linear, auto
+      vars:
+        ansible_python_interpreter: auto
+      ping:
+      register: linear_auto_result
+
 
 - name: integration/interpreter_discovery/ansible_2_8_tests.yml
   hosts: test-targets
   gather_facts: true
-  vars:
-    DISCOVERED_INTERPRETER_EXPECTED_MAP__ANSIBLE_lt_2_12:
-      centos:
-        '6': /usr/bin/python
-        '7': /usr/bin/python
-        '8': /usr/libexec/platform-python
-      debian:
-        '9': /usr/bin/python
-        '10': /usr/bin/python3
-        '11': /usr/bin/python3
-        'NA': /usr/bin/python  # Debian 11, Ansible <= 7 (ansible-core <= 2.14)
-        'bullseye/sid': /usr/bin/python  # Debian 11, Ansible 8 - 9 (ansible-core 2.15 - 2.16)
-      ubuntu:
-        '16': /usr/bin/python3
-        '18': /usr/bin/python3
-        '20': /usr/bin/python3
-
-    DISCOVERED_INTERPRETER_EXPECTED_MAP__ANSIBLE_2_12_to_2_16:
-      centos:
-        '6': /usr/bin/python
-        '7': /usr/bin/python
-        '8': /usr/libexec/platform-python
-      debian:
-        '9': /usr/bin/python
-        '10': /usr/bin/python3
-        '11': /usr/bin/python3
-        'NA': /usr/bin/python3.9  # Debian 11, Ansible <= 7 (ansible-core <= 2.14)
-        'bullseye/sid': /usr/bin/python3.9  # Debian 11, Ansible 8 - 9 (ansible-core 2.15 - 2.16)
-      ubuntu:
-        '16': /usr/bin/python3
-        '18': /usr/bin/python3
-        '20': /usr/bin/python3
-
-    DISCOVERED_INTERPRETER_EXPECTED_MAP__ANSIBLE_ge_2_17:
-      debian:
-        '10': /usr/bin/python3.7
-        '11': /usr/bin/python3.9
-        'bullseye/sid': /usr/bin/python3.9
-      ubuntu:
-        '20': /usr/bin/python3.8
-
-    discovered_interpreter_expected: >-
-      {%- if ansible_version_major_minor is version('2.12', '<', strict=True) -%}
-      {{ DISCOVERED_INTERPRETER_EXPECTED_MAP__ANSIBLE_lt_2_12[distro][distro_major] }}
-      {%- elif ansible_version_major_minor is version('2.17', '<', strict=True) -%}
-      {{ DISCOVERED_INTERPRETER_EXPECTED_MAP__ANSIBLE_2_12_to_2_16[distro][distro_major] }}
-      {%- else -%}
-      {{ DISCOVERED_INTERPRETER_EXPECTED_MAP__ANSIBLE_ge_2_17[distro][distro_major] }}
-      {%- endif -%}
   tasks:
     - name: can only run these tests on ansible >= 2.8.0
       block:
@@ -65,12 +27,6 @@
             fail_msg: "'ansible_python_interpreter' appears to be set at a high precedence to {{ ansible_python_interpreter }},
                       which breaks this test."
 
-        - name: snag some facts to validate for later
-          set_fact:
-            distro: '{{ ansible_facts.distribution | lower }}'
-            distro_major: '{{ ansible_facts.distribution_major_version }}'
-            system: '{{ ansible_facts.system }}'
-
         - name: test that python discovery is working and that fact persistence makes it only run once
           block:
           - name: clear facts to force interpreter discovery to run
@@ -215,16 +171,10 @@
           - name: Check discovered interpreter matches expected
             assert:
               that:
-                - auto_out.ansible_facts.discovered_interpreter_python == discovered_interpreter_expected
+                - auto_out.ansible_facts.discovered_interpreter_python == linear_auto_result.ansible_facts.discovered_interpreter_python
               fail_msg: |
-                distro={{ distro }}
-                distro_major= {{ distro_major }}
-                system={{ system }}
                 auto_out={{ auto_out }}
-                discovered_interpreter_expected={{ discovered_interpreter_expected }}
-                ansible_version.full={{ ansible_version.full }}
-            when:
-              - system in ['Linux']
+                linear_auto_result={{ linear_auto_result }}
 
           always:
           - meta: clear_facts