[ImgBot] Optimize images

[imgbot[bot]]

Beep boop. Your images are optimized!

Your image file size has been reduced by 56% 🎉

Details

File	Before	After	Percent reduction
/img/k.png	2.35kb	0.64kb	72.52%
/img/bar.png	7.34kb	2.42kb	67.03%
/img/stack-bar.png	16.94kb	5.63kb	66.76%
/img/dodge-bar.png	8.22kb	2.90kb	64.70%
/img/dodge.png	3.65kb	1.57kb	57.04%
/img/stack-column.png	5.96kb	2.65kb	55.51%
/img/radial-bar.png	10.42kb	4.69kb	54.95%
/img/column.png	3.41kb	1.55kb	54.67%
/img/radar.png	10.53kb	5.01kb	52.46%
/img/area.png	3.00kb	1.47kb	50.96%
/img/rose.png	6.91kb	3.39kb	50.90%
/img/gauge.png	6.58kb	3.30kb	49.80%
/img/line.png	2.94kb	1.48kb	49.58%
/img/double-axis.png	4.87kb	2.45kb	49.58%
/img/ring.png	6.39kb	3.23kb	49.47%
/img/pie.png	6.06kb	3.07kb	49.32%
/img/stack-area.png	5.01kb	2.66kb	46.84%
Total :	110.58kb	48.13kb	56.47%

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