Use isMac functionality from podman desktop API instead.

[cdrage]

Is your enhancement related to a problem? Please describe

We have this in the code:

const windows = os.platform() === 'win32';
export function isWindows(): boolean {
  return windows;
}

const linux = os.platform() === 'linux';
export function isLinux(): boolean {
  return linux;
}

const darwin = os.platform() === 'darwin';
export function isMac(): boolean {
  return darwin;
}

Describe the solution you'd like

We should replace it with the built-in Podman Desktop functionality here:

import { env } from '@podman-desktop/api'
env.isMac
``

### Describe alternatives you've considered

_No response_

### Additional context

From https://github.com/containers/podman-desktop-extension-bootc/pull/865#discussion_r1784841518