Make sure matrix_user_uid and matrix_user_gid are always set

If one runs the playbook with `--tags=setup-all`, it would have been
fine.

But running with a specific tag (e.g. `--tags=setup-riot-web`) would
have made that initialization be skipped, and the `matrix-riot-web` role
would fail, due to missing variables.

roles/matrix-base/tasks/main.yml

@@ -12,6 +12,13 @@
   tags:
     - setup-all
 
+# This needs to always run, because it populates `matrix_user_uid` and `matrix_user_gid`,
+# which are required by many other roles.
+- import_tasks: "{{ role_path }}/tasks/setup_matrix_user.yml"
+  when: run_setup|bool
+  tags:
+    - always
+
 - import_tasks: "{{ role_path }}/tasks/setup_matrix_base.yml"
   when: run_setup|bool
   tags:

roles/matrix-base/tasks/setup_matrix_base.yml

@@ -1,26 +1,5 @@
 ---
 
-- name: Ensure Matrix group is created
-  group:
-    name: "{{ matrix_user_username }}"
-    state: present
-  register: matrix_group
-
-- name: Set Matrix Group GID Variable
-  set_fact:
-    matrix_user_gid: "{{ matrix_group.gid }}"
-
-- name: Ensure Matrix user is created
-  user:
-    name: "{{ matrix_user_username }}"
-    state: present
-    group: "{{ matrix_user_username }}"
-  register: matrix_user
-
-- name: Set Matrix Group UID Variable
-  set_fact:
-    matrix_user_uid: "{{ matrix_user.uid }}"
-
 - name: Ensure Matrix base path exists
   file:
     path: "{{ item }}"

roles/matrix-base/tasks/setup_matrix_user.yml

@@ -0,0 +1,22 @@
+---
+
+- name: Ensure Matrix group is created
+  group:
+    name: "{{ matrix_user_username }}"
+    state: present
+  register: matrix_group
+
+- name: Set Matrix Group GID Variable
+  set_fact:
+    matrix_user_gid: "{{ matrix_group.gid }}"
+
+- name: Ensure Matrix user is created
+  user:
+    name: "{{ matrix_user_username }}"
+    state: present
+    group: "{{ matrix_user_username }}"
+  register: matrix_user
+
+- name: Set Matrix Group UID Variable
+  set_fact:
+    matrix_user_uid: "{{ matrix_user.uid }}"