Add Ruby 2.7 compatibility to Errbit

Since Errbit uses Rails 4, we need to specify an earlier version of the
`bigdecimal` gem in order to make Rails 4 compatible with Ruby 2.7. The
idea comes from pull request 1508 in https://github.com/errbit/errbit/.

On the plus side, we can now use Bundler 2.

roles/errbit/tasks/main.yml

@@ -8,12 +8,12 @@
  shell: "git clone https://github.com/errbit/errbit.git {{ errbit_dir }}"
  when: errbit_repo.stat.exists == False
 
-# TODO: Remove when we upgrade to bundler 2.x
-- name: Use bundler 1.x
- replace:
- path: "{{ errbit_dir }}/Gemfile.lock"
- regexp: ' 2.*'
- replace: ' 1.17.1'
+- name: Add Ruby 2.7 compatibility
+ template:
+  src: "{{ playbook_dir }}/roles/errbit/templates/UserGemfile"
+ dest: "{{ errbit_dir }}/UserGemfile"
+ owner: "{{ deploy_user }}"
+ group: "{{ deploy_group }}"
 
 - name: Create log folder
  file:

roles/errbit/templates/UserGemfile

@@ -0,0 +1 @@
+gem "bigdecimal", "~> 1.4.4"