Remove http_proxy_ args from the client module utils

The http_proxy_* args should be removed from the client module utils files. These args do not align with their corresponding parameters (proxy_host, proxy_port), which is confusing.

Since these utils are public, the change must be done as part of a major release

See https://github.com/ansible-collections/vmware.vmware/pull/261

Start by locating the client module utils files and reviewing the referenced pull request #261. Check how the public http_proxy_* arguments relate to proxy_host and proxy_port, then remove the mismatched arguments as part of the planned major release; the issue provides no specific test location.

Written by the indexing model from the issue text.