Remove feature flag for order votes

[vusirikala]

Description

This PR enables order votes by default, removes the order votes feature flag, and cleans up code that would run only when order votes are disabled.
However, the round manager tests WON'T pass. All the round manager tests pass only when order votes are disabled. Need to fix the round manager tests before this PR could be landed.

How Has This Been Tested?

Key Areas to Review

Type of Change

• New feature
• Bug fix
• Breaking change
• Performance improvement
• Refactoring
• Dependency update
• Documentation update
• Tests

Which Components or Systems Does This Change Impact?

• Validator Node
• Full Node (API, Indexer, etc.)
• Move/Aptos Virtual Machine
• Aptos Framework
• Aptos CLI/SDK
• Developer Infrastructure
• Move Compiler
• Other (specify)

Checklist

• I have read and followed the CONTRIBUTING doc
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I identified and added all stakeholders and component owners affected by this change as reviewers
• I tested both happy and unhappy path of the functionality
• I have made corresponding changes to the documentation

[trunk-io]

⏱️ 34m total CI duration on this PR

Job	Cumulative Duration	Recent Runs
rust-move-tests	13m	🟩
rust-move-tests	10m	⬜
rust-cargo-deny	4m	🟩 ⬜ 🟩
check-dynamic-deps	4m	🟩 🟩 🟩
semgrep/ci	1m	🟩 🟩 🟩
general-lints	1m	🟩 🟩 🟩
file_change_determinator	33s	🟩 🟩 🟩
rust-move-tests	18s	⬜
permission-check	12s	🟩 🟩 🟩
permission-check	9s	🟩 🟩 🟩

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