Update matrix-registration-bot, improve authentication config (#2723)

* Adjust to new mrb docker versioning

* Stabilze authentication

* fix lint

* Move & document mrb password usage

* Add clean cache role

* Document clean cache

* Fix lint

* Update CHANGELOG.md

* Automate access tokens

* Improve changelog

* Make use of mrb's function to fetch API tokens

* Adjust changelog

* Use ansible.builtin.file to clear directory

* Fix typo

---------

Co-authored-by: Slavi Pantaleev <slavi@devture.com>

roles/custom/matrix-bot-matrix-registration-bot/tasks/clean_cache.yml

@@ -0,0 +1,12 @@
+---
+
+- name: Delete cache files
+  ansible.builtin.file:
+    state: "{{ item }}"
+    path: "{{ matrix_bot_matrix_registration_bot_data_path }}"
+    mode: 0750
+    owner: "{{ matrix_user_username }}"
+    group: "{{ matrix_user_groupname }}"
+  with_items:
+    - absent
+    - directory