Module to generate Diffie-Hellman parameters (#32620)

* Module to generate Diffie-Hellman parameters

Implements #32577

* Add integration tests for openssl_dhparam

* Slightly refactor check to prevent unnecessary regeneration

* Fix code smell in tests

Highly annoying to have to do this again and again and again as the rules change during the game

* Using module.run_command() and module.atomic_move() from a tempfile.

* Remove underscore variable

Ansible prefers dummy

test/integration/targets/openssl_dhparam/tests/validate.yml

@@ -0,0 +1,32 @@
+---
+- name: Validate generated params
+  shell: 'openssl dhparam -in {{ output_dir }}/{{ item }}.pem -noout -check'
+  with_items:
+    - dh768
+    - dh512
+
+- name: Get bit size of 768
+  shell: 'openssl dhparam -noout -in {{ output_dir }}/dh768.pem -text | head -n1 | sed -ne "s@.*(\\([[:digit:]]\{1,\}\\) bit).*@\\1@p"'
+  register: bit_size_dhparam
+
+- name: Check bit size of default
+  assert:
+    that:
+      - bit_size_dhparam.stdout == "768"
+
+- name: Get bit size of 512
+  shell: 'openssl dhparam -noout -in {{ output_dir }}/dh512.pem -text | head -n1 | sed -ne "s@.*(\\([[:digit:]]\{1,\}\\) bit).*@\\1@p"'
+  register: bit_size_dhparam_512
+
+- name: Check bit size of default
+  assert:
+    that:
+      - bit_size_dhparam_512.stdout == "512"
+
+- name: Check if changed works correctly
+  assert:
+    that:
+      - dhparam_changed is not changed
+      - dhparam_changed_512 is not changed
+      - dhparam_changed_to_512 is changed
+      - dhparam_changed_force is changed