roles/nextcloud: Switch to Fedora package

Fedora now includes a packaged version of Nextcloud.  This will be
_much_ easier to maintain than the tarball-based distribution method.
There are some minor differences in how the Fedora package works,
compared to the upstream tarball.  Notably, it puts the configuration
file in `/etc/` and makes it read-only, and it stores persistent data
separate from the application.  These differences require modifications
to the Apache and PHP-FPM configuration, but the package also included
examples to make this easier.  Since the `config.php` is read-only now,
it has to be managed by the configuration policy; it cannot be modified
by the Administration web UI.

roles/nextcloud/vars/main.yml

@@ -1,25 +1,4 @@
 nextcloud_packages:
-- bzip2
 - ffmpeg
-- php
-- php-fpm
-- php-gd
-- php-gmp
-- php-intl
-- php-json
-- php-ldap
-- php-mbstring
-- php-opcache
-- php-pdo
-- php-pecl-apcu
-- php-pecl-imagick
-- php-pecl-zip
-- php-pgsql
-- php-process
-- php-smbclient
-- php-xml
+- nextcloud
 - python3-psycopg2
-- tar
-nextcloud_archive_name: nextcloud-{{ nextcloud_version }}.tar.bz2
-nextcloud_archive_url: >-
- https://download.nextcloud.com/server/releases/{{ nextcloud_archive_name }}