fix types of swiper-effect-utils.d.ts

[kudohamu]

This PR fix two type issues of swiper-effect-utils.d.ts.

1. change import of .d.ts file to import type

related: 30ce8e0

A declaration file cannot be imported without 'import type'. Did you mean to import an implementation file './types/index.ts' instead?

2. Fix invalid optional parameter declaration of createShadow.

In making this correction, I checked that suffix parameter is specified at all places in this repo where createShadow is called.

A required parameter cannot follow an optional parameter.

[nolimits4web]

t0ggles-create swiper

[t0ggles]

Task nolimits4web/SWIPER-149 was created

[t0ggles]

Task nolimits4web/SWIPER-149 status changed to Done

[nolimits4web]

Merged, thanks!