Add Optimization as a type of change (#11221)

* Add Optimization as a type of change. 
* Make the checkmark affirmative instead of disaffirming

.github/PULL_REQUEST_TEMPLATE.md

@@ -10,9 +10,10 @@
 ## Types of changes
 - [ ] Bug fix (non-breaking change which fixes an issue)
 - [ ] New feature (non-breaking change which adds functionality)
+- [ ] Optimization (provides speedup with no functional changes)
 - [ ] Breaking change (fix or feature that would cause existing functionality to change)
 
 ## Checklist:
 - [ ] Fixes a regression (If yes, please add `commit-id` or `PR #` here)
-- [ ] Documentation needed
-- [ ] Unit tests needed
+- [ ] Documentation updated
+- [ ] Unit tests added/updated