reordered block statements

roles/mastodon/tasks/system_setup/ruby.yml

@@ -1,8 +1,5 @@
 ---
 - block:
-  become: true
-  become_user: "{{ mastodon_user }}"
-
   - name: mastodon | Clone rbenv
     git:
       repo: "https://github.com/rbenv/rbenv.git"
@@ -59,4 +56,7 @@
     shell: 'export PATH="$HOME/.rbenv/bin:$PATH"; eval "$(rbenv init -)"; gem install bundler:{{ bundler_version }}'
     args:
       executable: /bin/bash
-    when: default_ruby_version is succeeded
+    when: default_ruby_version is succeeded
+
+  become: true
+  become_user: "{{ mastodon_user }}"