Velocity cleanup: remove feature flags for Feature_AdjustIndistinguishableText

[PankajBhojwani]

Summary of the Pull Request

Remove velocity feature flags for Feature_AdjustIndistinguishableText as it is AlwaysEnabled now

PR Checklist

• [x] Closes #13508
• [x] CLA signed. If not, go over here and sign the CLA
• [ ] Tests added/passed
• [ ] Documentation updated. If checked, please file a pull request on our docs repo and link it here: #xxx
• [ ] Schema updated.
• [x] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx

Validation Steps Performed

Everything still works