isolate homebrew operations from curl role

[sxa]

curl role is throwing errors on the new AWX server when run on Linux machines:

ERROR! couldn't resolve module/action 'homebrew'. This often indicates a misspelling, missing collection, or incorrect module path.
The error appears to be in '/runner/project/ansible/playbooks/AdoptOpenJDK_Unix_Playbook/roles/curl/tasks/main.yml': line 121, column 3, but may
be elsewhere in the file depending on the exact syntax problem.
The offending line appears to be:
- name: Install latest version of curl for MacOS
  ^ here

Since the curl role was intended for use when the package manager's version was too low (and that is unlikely to be the case for a homebrew installed version) this moves the homebrew install of curl to the common role for consistency with the Linux ones.

Note that this leaves the /usr/local/bin/curl symlink creation in the curl role for now but that could potentially be moved too.

Note that while this is possible a good change in isolation it doesn't nor resolve all of the problems as the same occurs for the zypper module in the GIT_Source role.

Checklist

• [x] commit message has one of the standard prefixes
• [ ] faq.md updated if appropriate
• [ ] other documentation is changed or added (if applicable)
• [ ] playbook changes run through VPC or QPC (if you have access)
• [ ] VPC/QPC not applicable for this PR
• [ ] for inventory.yml changes, bastillion/nagios/jenkins updated accordingly