Update Tip Styling on Lesson Plan

[dmcavoy]

• Tip icon are colored the correct tip color
• Add padding on the tip icon
• Try to better space the tips and activity section markdown

Updated based on feedback from the bug bash

[davidsbailey]

Cool! I am interested to see how well this heuristic performs. If this heuristic is not good enough, there are also some places where we render the element and then measure its height, like here:

code-dot-org/apps/src/templates/feedback/LevelFeedbackEntry.jsx

Lines 87 to 92 in ff60929

	const measureElement = element => {
	const DOMNode = ReactDOM.findDOMNode(element);
	return {
	height: DOMNode.offsetHeight
	};
	};

If you go that route, you have to be careful not to get into an infinite loop, because changing the width can change the height. There are ways to deal with this, but we can probably put off solving that for now.