## Issue being fixed or feature implemented
With #5525 , MNs shouldn't use Sentinel anymore.
## What was done?
In order to force them to remove Sentinel:
- `gobject submit` RPC won't accept triggers anymore.
- `gobject vote-conf` RPC isn't available anymore.
## How Has This Been Tested?
`feature_governance.py` and `feature_governance_object.py`
## Breaking Changes
Normally, only Sentinel should be broken.
## Checklist:
- [x] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [x] I have added or updated relevant unit/integration/functional/e2e
tests
- [x] I have made corresponding changes to the documentation
- [x] I have assigned this pull request to a milestone _(for repository
code-owners and collaborators only)_
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Co-authored-by: UdjinM6 <UdjinM6@users.noreply.github.com>
