Port admin actions extension to core API

Changes:
- Register admin actions API as core API.
- Remove extension code for admin actions.
- Leave rename of admin actions API 'post' data for future update which
  will be done with bump of microversion
  after port of all extensions to core API.

Partially implements bp ext-to-core
Closes-Bug: #1510620

Change-Id: Ic8804cff5fa46003d2991372c6eb2a854b886dec
3 files changed
tree: 5d971913889ff72aeb4fe1b00e757e443aefcaa7
  1. manila_tempest_tests/