`{a,b,c}` no longer considered a dynamic pattern

[amitdahan]

Bug Report

Starting with the newly released version 3.2.8 - {a,b,c} (sets bigger than 2) is no longer true for isDynamicPattern, while we only test for {a,b} (which still IS considered dynamic).

This broke exactly here:

https://github.com/mrmlnc/fast-glob/pull/344/files#diff-353cf32a130afd9d8b40a67a67f30b51434672caa8ab235726cbd0c82f65fc75R15

Expected behavior

isDynamicPattern('{a,b,c}') === true

[MurzNN]

Seems this is not fixed, because I can reproduce this issue with 3.2.10 too, here is my bug report: #351