🐞 fix for 10 - Hold Shift and ...

Adding a link to a different solution for 10 - Hold Shift and Check Checkboxes.
Fixed bugs and improved UX.

Author: marcoSven

readme.md

@@ -53,6 +53,7 @@ Here are some links of people who have done the tutorials, but in a different la
 * [Akinjide Bankole](https://github.com/akinjide/JS30days) used Node.js with [Jade](http://jadelang.net) to solve the exercises
 * [Adrien Poly](https://github.com/adrienpoly/javascript30-stimulus) a modest attempt to convert Drum Kit, Video Player, Local Tapas, TypeHead to [Stimulus JS](https://stimulusjs.org/) framework in a Rails App.
 * [Bogdan Lazar](https://github.com/tricinel/TypeScript30) all the JavaScript 30 written in [TypeScript](https://www.typescriptlang.org/)
+* [marcoSven](https://github.com/marcoSven) solution suggestion for [10 - Hold Shift and Check Checkboxes](https://github.com/marcoSven/JavaScript30/blob/master/10%20-%20Hold%20Shift%20and%20Check%20Checkboxes/index-FINISHED.html)
 
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