haproxy requests excessive resources by default

User story:

As a DBA when deploying a PXC DBaaS cluster haproxy requests are excessive by default

And as it can't be changed, I would recommend lowering the default to

Requests: cpu: 500m memory: 500M

So that this will help avoid wasting resources and reduce k8s cluster specs as by now 6G are needed only for haproxy to run small databases in k8s.

Acceptance criteria

• haproxy is default choice for PXC cluster
• haproxy default requests CPU 500m
• haproxy default requests memory is 500M
• Documentation updated to reflect these changes

Details

This is what we get by default in the haproxy section

Requests: 
    cpu: 1 
    memory: 2G

Recommended defaults would be

Requests: 
    cpu: 500m 
    memory: 500M