Corrected touch target boundaries for various chart types

[venkatbhoogarbh]

Fix: Corrected touch target boundaries and stack selection logic for Bar charts, Pie charts, Stack charts, and many more

[hannesa2]

Hm, I'm not sure if we bump minSdk to 24 only because of this. Please give me an argument to do so.

/home/runner/work/AndroidChart/AndroidChart/chartLib/src/main/kotlin/info/appdev/charting/renderer/BarChartRenderer.kt:60: Error: Call requires API level 24, or core library desugaring (current min is 23): java.lang.Iterable#forEach [NewApi]
        barData?.dataSets?.forEach {
                           ~~~~~~~

[hannesa2]

according to https://apilevels.com/

[venkatbhoogarbh]

I changed it appropriately to use a standard for-in loop, preserving full API 23 compatibility. Thank you for pointing that out!

[hannesa2]

Thanks a lot for your afford. As forks can't makes screenshot compare test, I made a copy of this PR #794 to enable this.
Additional I'll invite you, then you can push to upstream and can pull requests with screenshot compare machanism