This commit removes the unused methods _determine_version_cap and
_get_subcloud_users from the subclouds API and dcorch.
Test plan:
1. PASS: Run tox successfully
2. PASS: Confirm that there are no references to the removed code
3. PASS: Deploy a subcloud
Story: 2007082
Task: 51262
Change-Id: I697eca02fc6c7c33d07cf4cf5cec13b6c541f173
Signed-off-by: Raphael Lima <Raphael.Lima@windriver.com>
0b47eaac6a