Disable HA CI tests (#3097)

### Description
- Disable HA tests as the current impl. is obsolete
- Make master_template consistent (in
nvflare/lighter/templates/master_template.yml and
nvflare/lighter/impl/master_template.yml)

### Types of changes
<!--- Put an `x` in all the boxes that apply, and remove the not
applicable items -->
- [x] Non-breaking change (fix or new feature that would not break
existing functionality).
- [ ] Breaking change (fix or new feature that would cause existing
functionality to change).
- [ ] New tests added to cover the changes.
- [ ] Quick tests passed locally by running `./runtest.sh`.
- [ ] In-line docstrings updated.
- [ ] Documentation updated.

Co-authored-by: Sean Yang <[email protected]>