fix: getRecentDot ignores disabled dots

[petr-kratochvil]

Hello, i had an issue with multiple dots on slider and some of them being disabled. Then clicking on the slider would sometimes move one of the enabled dots, but sometimes wouldn't do anything - that was in the case, when the closest dot (which would normally move) was disabled.

I propose a fix which ignores disabled dots when looking for the closest dot (getRecentDot function).

Thanks

Petr Kratochvíl

[NightCatSama]

Released in 3.2.15.