Enable pipelining for faster playbook execution

Some quick tests show a massive improvement.
I ran the following: ansible-playbook playbooks/everything.yaml
And the execution times without setting the option were:
- 1m25.5s
- 1m25.1s
- 1m25.8s
And with the option set to true:
- 25.5s
- 24.1s

Also see:
https://www.redhat.com/sysadmin/faster-ansible-playbook-execution
https://www.ansible.com/blog/ansible-performance-tuning
https://docs.ansible.com/ansible/latest/reference_appendices/config.html#ansible-pipelining

ansible.cfg

@@ -1,2 +1,3 @@
 [defaults]
 inventory = ./inventories/hetzner/hosts.yaml
+pipelining = true