feat(playbooks): wkthmltox for Ubuntu 20 (frappe#1019)

* Updating file to support Ubuntu20.04 LTS
* Update main.yml
* Update bench/playbooks/roles/wkhtmltopdf/tasks/main.yml
* Removed checksum from Ubuntu 20

Co-authored-by: gavin <gavin18d@gmail.com>

bench/playbooks/roles/wkhtmltopdf/tasks/main.yml

@@ -20,6 +20,12 @@
     force: yes
   when: ansible_os_family == 'Debian'
 
+- name: download wkthmltox Ubuntu 20
+  get_url:
+    url: https://github.com/wkhtmltopdf/wkhtmltopdf/releases/download/0.12.5/wkhtmltox_0.12.5-1.focal_amd64.deb
+    dest: /tmp/wkhtmltox.deb
+  when: ansible_distribution == 'Ubuntu' and ansible_distribution_major_version == '20'
+
 - name: download wkthmltox Ubuntu 18
   get_url:
     url: https://github.com/wkhtmltopdf/wkhtmltopdf/releases/download/0.12.5/wkhtmltox_0.12.5-1.bionic_{{ "amd64" if ansible_architecture == "x86_64" else "i386"}}.deb