* validate staircasing dates
* validate staircasing percentage totals
* don't show both similar validations at once
* only validate against saledate when saledate present
* format numbers in error message
* add tests for staircasing validations
* linting
* don't block log creation on staircasing date errors
* combine similar validation methods
* update tests
* fix syntax
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Co-authored-by: Carolyn <carolyn.barker@softwire.com>