## Issue being fixed or feature implemented
When expecting a hard fork, we manually calculate activation heights.
## What was done?
Returning expected activation height for BIP9 softporks in `locked_in`
status in `getblockchaininfo` RPC.
## How Has This Been Tested?
## Breaking Changes
n/a
## Checklist:
- [x] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have added or updated relevant unit/integration/functional/e2e
tests
- [ ] 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)_
