[Task]: Remove unecessary if condition when setting margins via Gotenberg

[matthiashamacher]

If you would set any of the margins, except marginRight to 0 the if condition would evaluate to false and therefore the margins won't be set. By checking all with isset the condition would be true if any one of them is set and the margins will be applied

[kingjia90]

Probably we don't need this IF at all because of

web-to-print-bundle/src/Processor/Gotenberg.php

Lines 122 to 127 in b278773

	$chromium->margins(
	$params['marginTop'] ?? 0.39,
	$params['marginBottom'] ?? 0.39,
	$params['marginLeft'] ?? 0.39,
	$params['marginRight'] ?? 0.39
	);

If margins() method is not called here, it's going to be 0.39 by default anyways, so this null coalescing would cover it

[matthiashamacher]

@kingjia90
Good Point. I've updated the PR and removed the if condition.