slidesPerView does not work with anything other than integers

[goellner]

Describe the bug
slidesPerView accepts floats, but only works with integers

Expected behavior
It should properly compute the widths. Currently its not possible to see the full last slide, if you have slidesPerView set to 2.5 for example.

Information

• Tiny-Swiper Version: all
• Reproduce example：https://stackblitz.com/edit/tiny-swiper2-demo-space-between-slides-nd7unu?file=index.html