Removing high-dpi check because it is not necessary anymore (and wrong implemented)

[Falke-Design]

With the commit 2e2239e a fix for screens with 150% resolution (#81) was added:

leaflet.browser.print/src/leaflet.browser.print.sizes.js

Lines 126 to 131 in 2e2239e

	var margin = this.getPageMargin() * 2 * (window.devicePixelRatio || 1);
	size.Width = Math.floor(size.Width - margin) + 'mm';
	size.Height = Math.floor(size.Height - margin) + 'mm';
	return size;

With the V2 rewrite the logic was implemented wrong. Before the devicePixelRatio was added to the margin and subtracted from the size, now it is multipled with the size.

leaflet.browser.print/src/leaflet.browser.print.helpers.js

Lines 83 to 92 in 2378e6e

	var topbottom = orientaion === 'Portrait' ? parseFloat(pageMargin.top) + parseFloat(pageMargin.bottom) : parseFloat(pageMargin.left) + parseFloat(pageMargin.right);
	var leftright = orientaion === 'Portrait' ? parseFloat(pageMargin.left) + parseFloat(pageMargin.right) : parseFloat(pageMargin.top) + parseFloat(pageMargin.bottom);
	var height = Math.floor(size.Height - topbottom);
	var width = Math.floor(size.Width - leftright);
	size.Width = width * (window.devicePixelRatio || 1) + 'mm';
	size.Height = height * (window.devicePixelRatio || 1) + 'mm';
	return size;

Which causes that for displays with 150% scale, the map is rendered on two pages:

Removing the devicePixelRatio fixes the issue:

I checked out the old commit 2e2239e to see for which reasons the devicePixelRatio was added but it looks like it was never necessary? Maybe the browsers have changed printing too

leaflet.browser.print/src/leaflet.browser.print.sizes.js

Lines 126 to 131 in 2e2239e

	var margin = this.getPageMargin() * 2 * (window.devicePixelRatio || 1);
	size.Width = Math.floor(size.Width - margin) + 'mm';
	size.Height = Math.floor(size.Height - margin) + 'mm';
	return size;

Here are images of the commit with and without devicePixelRatio:

With devicePixelRatio: smaller margin and additional content is on the first page:

Without devicePixelRatio the margins are equal:

@Igor-Vladyka are you able to find out if the changes of 2e2239e are still needed?

[Igor-Vladyka]

@Falke-Design nope, I don't remember why it was needed in a first place. Nice, thanks.