(#22414) Rename for consistency `$input-bg-disabled`, `$input-bg-focus`, `$input-border-color-focus`, `$input-box-shadow-focus`, `$input-color-focus`, `$input-color-placeholder` to `$input-disabled-bg`, `$input-focus-bg`, `$input-focus-border-color`, `$input-focus-box-shadow`, `$input-focus-color`, `$input-placeholder-color`, respectively