Line break/long text in helper-text should keep intendation

[rugk]

Especially when you have a lot of text/small UI width the helper-text CSS class is going to wrap and the indentation is broken beginning from the second line of text.

This is not what the Photon design wants (I guess), so we should find a way to begin the second line of text at the same X position.

Relevant design doc

https://design.firefox.com/photon/patterns/nesting.html
https://design.firefox.com/photon/patterns/helpers.html

[tdulcet]

I think this is related, when using the line CSS class it also puts extra unwanted margin at the end of some subelements, such as links (<a>) and <code>:

Here is the offending rule:

AutomaticSettings/css/photonOptions.css

Lines 115 to 118 in fce7d28

	.line > * {
	/* https://design.firefox.com/photon/visuals/grid.html#spacing */
	margin: 0 8px 0 0;
	}