Magic methods for DOMPDF instance

[erikn69]

is possible to provide access to all dompdf methods using __call magic method?
This PR avoid adding a method wrapper for each dompdf method

• provide access to setCallbacks method #888
• Method setHttpContext for avoid using getDomPDF #871

Those PRs will be avoid if this PR is posible

Also, after this, setPaper could be deleted

laravel-dompdf/src/PDF.php

Lines 74 to 78 in cdd4990

	public function setPaper($paper, string $orientation = 'portrait'): self
	{
	$this->dompdf->setPaper($paper, $orientation);
	return $this;
	}

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UPDATE: Test and phpDoc added