[🐛]: current polyfills scope are incorrectly cover Safari 13 features

[ala-n]

Safari 13 on iOS does not support Resize Observer, while it is not being poly-filled for that browser

To Reproduce

1. Open ESLScrollbar samples page on iOS Safari v13
2. Observe the page
3. Observe console

Current behavior There is no scrollbar on the page. Resize Observer missing exception is in console

Expected behavior Built-in polyfill or correct recommendation to polyfill ResizeObserver

Environment

• OS: iOS
• Browser: Safari <13

[ala-n]

FYI: @AlexanderBazukevich

[abarmina]

Close this issue as it isn't reproduced on Safari 12.1 and 13.1