Hello guys,

This PR contains upgrades to the check-svg bot. The bot will now:

• Not check for <style> tags in the SVG. Since the optimizer bot will prefix the classes with the file's name, the class name will be unique from now on => avoid issues of clashing class names from using multiple SVGs inline within HTML.
• Check for stroke-width in the property and styles of the elements. After some testing, I found that Icomoon will warn us about strokes based on the presence of the stroke-width property/style.

Test: N/A

EDIT: I've removed the stroke-width check. Having it in would require refactoring the script to almost similar as peek-bot. I think having peek-bot checking for strokes should be enough. Let me know what you guys think. If you think having check-svg warn them is better (since it's earlier), let me know.