Check the imagick *extension* version
Check the imagick *extension* version

We were checking the imagick library version in relation to the availability of the clone keyword, but it was actually the extension that removed support. This update modifies the version check to look at the extension version.

Addresses #1296

BrunoDeBarros/dompdf,nathanntg/dompdf,dompdf/dompdf,dompdf/dompdf,BrunoDeBarros/dompdf,nathanntg/dompdf